After 4 days stuck at 300-400 elo i have finally reached 500 elo.
My tips in case you're stuck at 200-400 elo. Just keep doing puzzles daily, analyze the matches you lost and play them again vs a bot, learn one opening for white and one for black, not too deep just the basics or the first few moves and 15|10 matches another thing that i did but I'm not sure if it works is dual n back exercise.