"...you're aligned with the idea that "climate change is fake"

This inaccurately characterizes me and the researchers in the OP. Indeed, it's a mischaracterization of scientific research into climate. No one I know has ever claimed that 'climate change is fake'. The factual statement is that anthropogenic (human caused) climate change is fake. More to the point, well asserted in the paper linked in the OP, is that there isn't a damn thing we can do about climate change, because forces far above our pay grade (such as the output of the sun, and the wobbling of Earth's orbit) are responsible for climate constantly changing, and not a damn thing we can do will stop that from happening.

"which do you prefer in your own financial and political interests..."

I don't. I am not a zealous acolyte of any religion or claim. I observe the actual data, and seek to surmount whatever is real and actual that might impact me or mine negatively. Because I note that humanity is extraordinary, uniquely apprised of capacity to reason and understand, and availed of the panoply of technology that comes of understanding, I highly value all humanity and the society we create. I prefer that we understand what is real and make decisions and apply ourselves to prevent catastrophic consequences that will surely lay us waste if we instead believe lies and do stupid things - like pay taxes to the tune of $275T between now and 2050 to appease the sky gods, or smth. The gods will not be appeased. That's what the paper's about.

"...do you understand yourself how GHG maintains habitable temperature on Earth? could you explain it to me as if I were 14 years old to make sure that we're on the same page?"

Lindzen and Happer are physicists that have spent their careers researching exactly that, and the paper linked in the OP is written for laymen. It is exactly the explanation you are seeking. The graph that is the titular image for my post shows exactly how CO2 and GHG's maintain habitable temperature on Earth, and the authors explain that the ~30w/m^2 they prevent from radiating into space is why the Earth isn't an icy, barren waste.

"could you state why you think any of the recent and popular studies saying that climate change is real isn't scientifically reliable?"

The first reason is that some years ago I had an uninformed opinion provided to me by corporate media. When I mentioned my suspicion that human industrial CO2 output could be having the claimed effect on climate to a friend I respected deeply, they pointed out that I was largely ignorant of the actual research, the hard data, and was falling for a money scam. While I was not swayed by that alone, I respected them enough to actually do some research, because they were right to point out I had not and my opinion was based on nothing but bare assertions.

WattsUpWithThat.com is a site where climate scientists discuss research, and the massive biases that research funders with a stake in the ~$275T AGW scam create. It was revelatory. I saw that CO2 has been orders of magnitude higher in the past, while ecosystems thrived. In the recent past there were also times when temperatures have been a few degrees higher, such as during the rise of Rome, and during the medieval warm period, when crops were able to be grown during longer seasons, and all the ills of inclement wintry temperatures were reduced, with obvious beneficial effects on human civil society. But what I found very convincing was the record of sea level rise and fall during the last couple million years, which is well documented and a record written in stone, not easily misinterpreted.

What that revealed to me is that we are today at the approximate height of sea levels that have serially risen and declined quite reliably over hundreds of millennia, and none of these changes were caused by CO2 emissions from human industry. It is very true that climate changes, but the sea level record shows that we have nothing to do with it, and rather than facing a dramatic rise in sea level - which would be catastrophic, as it has been over and again in the past - we face the very opposite situation, in which the oceans will be increasingly locked up in glaciers (much like CO2 has been locked up in coal and other minerals over hundreds of millions of years. CO2 levels are today at the lowest point they have ever been on Earth) and the sea levels will decline rapidly.

We are in an ice age. We are in an interglacial phase of an ice age, but the continental glaciers will soon return, because that is what climate naturally is doing over these last few million years, and not only is there nothing we can do about that, but we don't even well understand why this cycle began a few million years ago.

This utterly convinced me that the AGW scam was exactly that, a scam, and, like all scams, was going to do everyone that fell for it enduring harm. I think the best aspect of my environment, and that of my beloved sons, is civil society, an incredible boon to all humanity, and something I want to prosper maximally to increase the felicity of my sons and the future they will live in. Falling for a global scam will deprecate civil society, and degrade the conditions my sons and their myriad peers will enjoy as long as they live. This is why I speak out about it.

"...let's pretend for a moment that I think this study you've shown is 100% scientifically accurate. should I then think that global warming as a whole is a scam?"

Global warming is not an accurate characterization of Earth's climate, because, as you can easily confirm with trivial search of internet resources, climate both warms and cools. Climate change is not a scam. Claiming we have anything to do with climate change is a scam, and this can easily be confirmed by simply noting that sea levels rose >100m betwee 20kya and ~7kya. Dramatic global warming is a natural climactic variation, and not caused by industrial CO2 releases. Humanity didn't start releasing significant (~3% of the CO2 produced globally by all processes) CO2 until ~1950. Most of the CO2 produced every year comes out of volcanoes - and ~80% of volcanoes are underwater, where we know very little about them, what they're doing, how many of them there are, or even where most of them are.

"Anthropogenic" does mean of environmental change in general after all."

Anthropogenic does not mean environmental change. Anthropo refers to humanity, from the Greek.

"anthropo-
before a vowel, anthrop-, word-forming element meaning "pertaining to man or human beings," from Greek anthrōpos "man; human being" (including women), as opposed to the gods, from andra (genitive andros), Attic form of Greek anēr "man" (as opposed to a woman, a god, or a boy), from PIE root *ner- (2) "man," also "vigorous, vital, strong."

--https://www.etymonline.com/word/anthropo-

Genic refers to origin, also from the Greek.

"-genic
word-forming element meaning "producing, pertaining to generation;" see -gen + -ic."

--https://www.etymonline.com/word/-genic

So, anthropogenic means 'human caused'. That is why it is the defining objection of actual climate scientists to the claim that industrial CO2 output is causing temperatures to rise. Temperatures have risen and fallen on Earth for billions of years, and we didn't cause any of that. It's preposterous, completely false and not based on any scientific evidence at all, to claim the ordinary climactic variations today ongoing are anthropogenic. That is the central point of Lindzen and Happer's paper: human agency is not causing climate change - and human agency cannot significantly affect natural climactic processes, which is why they provide the calculation that fully realizing Net Zero by 2050 will only affect atmospheric average temperature by .13 degrees Fahrenheit, which is an infinitesimal and negligible impact on climate that will save nobody and nothing, but will make scammers inconceivably rich from the ~$275T they will extract from us to destroy our economy and turn civil society into a hellish dystopia.

I am unable to avoid the conclusion that you did not read the linked paper by Lindzen and Happer. Many of the questions you asked are answered in that paper. I humbly suggest that your lack of knowledge is the result of your lack of looking into these matters beyond corporate media claims, just as was mine less than a decade ago. It is a trivial matter to look at the data for global temperatures and CO2 levels for the last 600M years. That information is in the linked paper. All the claims made by the authors of the paper are easily verifiable. You haven't attempted to disprove any of them, and I don't think you even know what they are because you haven't read them.

The only reason you don't understand that they're telling you the truth is because you have only heard what the AGW scammers are telling you in the process of scamming you. While I realize that is unpalatable, because as Mark Twain pithily observed, it is easier to fool a man than to convince him he's been fooled, you are being scammed, and I don't want you to suffer the consequences of being scammed because I care about the world my sons will inherit from me, and they need allies to stop the steal, the theft of the blessings of civilization that is the birthright of humanity, and that includes you.

Please read the linked paper. Disprove anything asserted therein you disagree is factually correct with evidence that shows it is factually incorrect. If you're right, you'll change my mind. However, that is what I set out to do nearly a decade ago, and what convinced me that people aren't changing Earth's climate, because the natural forces controlling climate make human industry laughably puny.

Thanks!