Hey there.
I can help you with cash game strategy. Focus on these first and you will save a lot of time and effort.
pokerstars school has really upped the level of their new content in terms of reliability. They have Pete Clarke who is an excellent coach and also a content creator for Run It Once. Getting his knowledge for free is honestly a steal.
This is as good as free stuff gets and I would rely on his video series as your main resource for 6max cash:
https://www.pokerstarsschool.com/lessons/6-max-cash-game-guide-dealing-with-limpers/1182/
And here is the text format course that goes hand in hand with the videos:
https://www.pokerstarsschool.com/lessons/opening-the-pot/1019/
If this is too advanced for you then I recommend starting here and going in order:
https://www.pokerstarsschool.com/courses/
I also recommend "From the Ground Up" which is a $50 course for 6max from Run It Once and simply amazing value, it's also by Peter Clarke.
I will state that this is not an easy course to follow and he goes pretty fast, especially if you haven't learned much about poker in which case pokerstars school (with anything by Pete Clarke) will be more than enough for now. It's not something you can watch casually, you will need to pause/rewind it a lot and do a lot of rewatching and additional studying. He simply gives you a solid theoretical framework to build on, but it's aimed at slightly higher level play than the lowest micros imo. It's more advanced than his youtube videos.
After you've got a good foundation I recommend investing in something like Upswing Poker.
You can read the free Upswing
poker articles, they are excellent. If you're a beginner a lot of them may be confusing to you but you will find as you pick up bits of info all the pieces of the puzzle will start to fit together as you re-read them several times (make sure to look up concepts you don't understand in these articles).
If you want even more good free content Splitsuit has Pokerbank on youtube and also free articles, he is one of the content creators for Red Chip Poker. He is very easy to follow and breaks concepts down so anyone can understand them.
Johnathan Little is another good source of great videos on youtube
Blackrain79 has some good content, free pdf's, and articles for micros.
I would say focus on Pete Clarke's free content for now + Pokerstars School, and look at blackrain79's Massive Profit at the Micros pdf ("Massive Profit at the Micros" is a bit dated now, but it's a solid beginner foundation). And read / watch content from Upswing / Jonathan Little / Splitsuit for fun on the side.
Upswing's $7 "Postflop Gameplan" is also a very nice "cheat sheet" of sorts to see you through while you learn a more in depth strategy.
For bankroll management:
Have at least 30 buy ins for whatever level you're starting to play at. Set a stop loss for times when you start losing or tilting (usually 2 or 3 buy ins).