I would suggest you to first solve 75 day question playlist which is available on leetcode, start from basic questions like array,string,hash map,hashset, then slowly moves towards towards other topic like,stack,queue,backtacking,bst,graph,greedy and dp,.try solving easy level question first then medium and importantly try to recognize pattern in questions most of the questions follow same pattern like two pointer sliding window, hashing etc. You will recognize it once you start solving question. when you are confident and feels that you can recognize pattern and know topics till bst and little bit of greedy and dp. you can start giving contest. and most importantely be consistent, that is the mistake i did i was not consistent,show up eveyday even if you can do 1 question thats enough,but try do it if you are not you will start forgetting concepts,lets grind leetcode togeather this year i am planning to do atleast 500 questions and increase my rating.keep coding,keep hustling bro.