I am very weak in quants only able to do 2-3 questions with accuracy what to do in 50 days to score well

what i think you should do is see which topics are weak or choose 4,5 topics and practice some 50 questions per topic

Focus on simple arithmetic topics first and get to a level where you can solve medium level questions in those topics. This alone will give you 5-6 questions for sure. Meanwhile look for the easy questions in other topics like algebra, geometry, P&C, etc. and learn how to solve them.

take my advice , there is a youtube channel called mba pathshala. complete the whole arithmetic by that channel and try to complete geometry simultaneously, give a lot of time to these topics.