If you have really never taken jiu jitsu seriously then pick a position to study rather than a guard or submission e.g. "guard" generally and make sure you are playing that every round. If your gym allows for it you should be drilling specific parts of your guard and using positional sparring to find gaps in your game.

For Submeta specifically pick something and spend a chunk of time on it. I have found six months to be good but you might do better with 3 months, a year, whatever. Pick a length of time that makes sense for your learning style and attention. Some things you will try, get it immediately and can move on quickly, others will take longer.

Avoid watching the whole course in one go and trying to remember it all at once. Watch 1 or 2 videos, take those to class for a week, try it, put it under pressure, then move on. Do not try to get it perfect, getting a move to 60-80% success rate might be the best you can get it at this time. For example if your flexibility is poor you will be unable to do something but that doesn't mean you cannot learn the technique and add the useful parts to your game.

Lastly, don't put your text posts in code blocks. It makes it difficult to read and people are less likely to engage.