It's not the same with iPhone, 2GB barely takes me a week, without even opening a video online.

I'd say check the background apps you have running, unlike android that you can flip all apps off at a go you have to manually take the apps off from working and so if you open apps and just leave them background running can eat up your data.

Another frustrating reason is the battery. One can't survive with an iPhone without a good power bank, especially when the battery health has dropped below 70% like mine.

Once it drops below that point it is advisable to buy a new battery or get yourself a new phone, Samsung batteries ain't any better than IOS though, just mentioning because they are the rivals in the phone industry now