Help me guys!!!

I have been into codeforces from September end and yesterday attended the div 3 contest solved the first question , failed in test case 2 in 2 question and tle in 3 question . I have gave 5-6 div 2 and have been able to solve only A for those. I have touched 800 and it has been currently dropping from past 3 contests I have started solving problem set for div 2 As and Bs. Also div 3 A/B/Cs. Please suggest me to grow to upper pupil or atleast pupil till this year end.