How to prepare for Div 2 competitions?

Hello everyone,

I am a newbie to the CP world and have been recently promoted to Division 2 after participating in 3 rated contests on CodeChef. I have a good understanding of Data Structures and Algorithms but no experience of Competitive Programming. Can you guys suggest me some good resources/topics to prepare for the Div 2 contests on CodeChef?

Solve 50-70 problems for each difficulty level