What can I do in 20 days to clear MMMUT examination?

The level of difficulty of MMMUT entrance is not much. To score well in the examination, your basics should be clear. 

• For Physics and Chemistry, you should solve NCERT Numerical Qs. 
• For Mathematics, you should prefer Objective Mathematics of R.D Sharma. 

Also, familiarize yourself with the UPSEE test paper and give mocks to form a time management strategy.