Q1. If you trying to beat tough games, no matter if live or online, you need a strong theoretical approach to the game. You need to know how GTO is played and use it as your baseline.

Even if you are deviating from GTO a lot in your actual games by exploiting, you need to understand GTO in order to make good exploits.

Q2. Become obsessed with poker, create a studygroup and surround yourself with other people that share the same goal as you. Get a lot of different inputs of how worldclass players approach the game etc.

Grind/Learn/Eat/Sleep repeat for quite some time, and build up a stronger wall of wisdom about the game brick by brick. Be prepared of setbacks and don't become lazy.

Does this person bluff? Do I have better hands to call with in this spot? Some times you can be at the very top of your range, but the person never ever bluffs, so your literally over folding as an exploit. You make money because they will not over fold, but call too wide.

To be one of the best live pros, gotta learn how to navigate multiway pots. Some times the correct strategy is to play reall tight, but even fish will not give you action when you get AA if you folded everything for the last hour. The best live plays generally play really tight, but are very fun to be around socially, so fish give them action.

Above you can find pretty good answers. However it is missing one important part - live reads or psychology. Some really good live players aren't perfect in strategy but they are very good at reading people.
So don't forget about it

I find it sort of impossible to approach my game like that.

Then don't. The optimal amount of effort is when you're challenged a proper amount. Do what feels comfortable but also properly challenging, play/study 5k hours or so and let us know what you found. :)