MCA

Dear Adarsh,
MCA has a very high value in India. But if you do it from a Regular University and not an Open university as due to high competition in getting jobs, there is no value for doing MCA from Open university. Also it depends on your skills as degree only gives you knowledge but experience gives you necessary skills which are important for your job as well as your future. So reply me about your present qualification and I will advise yiu further. Good bye !!

Check the link and filter the best colleges according to ratings :
https://it.shiksha.com/mca-colleges-in-pune-categorypage-10-98-47-0-0-174-114-2-0-none-1-0#cateSearchBlock

1. Department of Computer Science University of Pune
2. School of Computer and Systems Sciences JNU New Delhi
3. School of Computer and Information Sciences University of Hyderabad
4.NIT Trichy
5. Birla Institute of Technology Jaipur
6. NIT Surathkal
7. MNNIT Allahabad
8. PSG College of Technology Coimbatore
9. NIT Rourkela
10. ITM University Gwalior

since u r weak in mathematics,i think u also weak in program coding.
mca and msc it.both required mathematics knowledge.without logic u can't do anything.
if u are medium or gd in eng communication then u go MBA IT.

BCA
1) AIMS Bangalore
2) Prestige Institute of Management and Research Indore
3) IIMC Hyderabad
4) Satya Institute of Media and Management Lucknow
5) Aryans Group of Colleges Mohali
MCA
1. Department of Computer Science University of Pune
2. School of Computer and Systems Sciences JNU New Delhi
3. School of Computer and Information Sciences University of Hyderabad
4.NIT Trichy
5. Birla Institute of Technology Jaipur
6. NIT Surathkal

Yes you can, if your backlogs extend your degree duration then it problematic otherwise if you cleared all the backlogs within standard degree duration then its fine

MCA course is specially designed for computer graduates and robotics is a part of mechanical , there is no course named as MCA in robotics, you can pursue BE Btech in robotics