Dos and Don'ts for improvement.

Most important advice: have fun! Chess is supposed to be a fun game.
Second: Make a decision to learn from you games. That means that you take a look at your games, and try to find improvements to both yourself and your opponent.
Third: Do tactical exercise (puzzles) and learn the basic mating patterns.
Don't try to learn openings. It is a waste of time until you have improved. Stick to the general opening principles (centre & development). Play 1.e4 with White, and 1.e4 e5 with Black.

Study/drills like puzzles or checkmating patterns and some basic tactics like forks and stalemate traps
Play rated rapid games with enough time for you to think through moves. This is key to develop your calculation skills.
Learn a basic opening and master it. One or two for black and one for white. You need to really understand the why/goals of the opening and not just the how. YouTube is really helpful for this.
Review your games. Take one or two learning takeaways from every game and go through them. And make a conscious effort to apply them moving forward.
Change your mentality during the game. Don’t just think of your moves in a game. Break down your opponent’s. Every move they do has an idea behind it. Find it and counter. (Hence the longer games).
I know it looks like a lot but you don’t have to do these everyday. Just do what you can in your time allowance. Bottom line is just have fun. I have fun doing all this because it’s like a complex puzzle.

Improving Your Chess - Resources for Beginners and Beyond…
https://www.chess.com/blog/RussBell/improving-your-chess-resources-for-beginners-and-beyond

Learn and apply the most important principles of chess. - (core of my teaching)
Always blunder-check your moves.
Solve tactics in the right way.
Analyze your games.
Study games of strong players.
Learn how to be more psychologically resilient.
Work on your time management skills.
Get a coach if you can.
STAY AWAY from Bullet and Blitz chess...
You learn 10times the amount from a slow game than a skittles game. You foster and train correct analysis techniques in slower time controlls... You don't in Bullet and Blitz.
Faster time controls is something you do when your advanced
Run from anyone who says otherwise... when you see the all to familiar post "I'm 2000 elo here at Chess.com played my first OTB tournament and got beat by a 1000 elo player .... think of my words.