How to improve at chess

@1
"My current chess rating for rapid is 600-700." ++ Play more rapid, preferably 15|10. Analyse your lost games. Blunder check before you move.
"My bullet rating is about 800." ++ Do not play bullet.
"Usually I play 10 games a day. Mostly being bullet." ++ Better play 1 game 15|10.
"I have been stuck at that rapid rating for 3 months." ++ Play rapid instead of bullet.
"How do I improve?" ++ Analyse your lost games and learn from your mistakes.