Hey Deepak

To start with- Practice the past few year question papers and sample papers. You can check out the pattern of the exam from https://engineering.careers360.com/articles/upsee-exam-pattern

Then you need to focus on the important topics for the exam (you can get it from https://engineering.careers360.com/articles/upsee-syllabus ).

Now you just have to keep revising and solving the papers in the stipulated time limit. You will learn alot (if not everything) if yiu start right now with full dedication(however try to get 6 hours of sleep till the exam because health comes first and a healthy mihnd is very important to score well)