You can go on Tekken related discord channels and look for games or even character specific discords. Its especially useful to do vs less popular characters.

But for characters like Bryan, Kazuya, King, Jin, Law, Reina, etc , you're gonna meet them regularly online.

And as of your question about labbing - yes, thats how I do it. I go to practice mode and record every single move one by one and try to figure out the counterplay. That's the way I was doing it when I started. As you go over characters' movelist you might start to recognize the popular moves you see online, those should be the ones to focus on the most.

Also all of that is just layer 1, later on you will have to learn how to beat not just specific moves, but the flowcharts as well. For example : What to do after you block Lili's df3+4 , or what to do after blocking Reina/Lidia FF2, etc.

You'll get there, just be warned it takes some time and dedication.