As I don't fully understand investing on Hive and increasing my staking yet

To explain this, let us take a look at Hive Power. When you turn your liquid Hive into Hive Power, that is what I mean staking. That process, you are investing in Hive. Because you are coverting your liquid Hive into staked Hive (Hive Power). So you get the process now.

I think Hive should be like a side hustle for people from a poor or middle class background while you'll still invest back into Hive, nothing beats personal growth.

This is awesome point here... taking it as a side hustle while still being focused on your personal growth. and how much we grow personally will be a reflection on our Hive account.

Thanks for your opinion. It is very much appreciated.