First, if you want to improve keep it fun. If you aren't having fun, you won't play enough to get better.
Consider the $3 per month Gold membership, if you can afford it. That will give you access to the game analysis, more puzzle rush, tactics and lessons.
Use consistent openings so you start to learn how to avoid getting in trouble early. Spend a little bit of time in the Openings area of the site to learn the basics, but not too much. Initially, you just want to learn a few moves to get you through the opening in a decent position without getting in trouble. When you get knotted up early, us Openings and analysis to learn the move or moves that would have avoided the problem. Write it down at first, so you don't forget.
Warm up for 15 minutes before playing live games by practicing tactics or playing puzzle rush. It gets you into chess mode. Always review the ones you get wrong. Over time you will begin to recognize more complex tactics and solve puzzles more quickly. Tactics are the heart of chess.
Finally, view every loss as a gift. You got a free lesson. Winning feels better, but I learn much more from replaying my losses and understanding what I did wrong.
It's like anything in life if you want to get better at something you got to spends hundreds of hours practicing doing it. I have dyslexia so if I can get better you can too. I watch these climbing the rating ladder video's to get better
youtube https://www.youtube.com/watch?v=U2huVf1l4UE