I am getting 139 I cat however only 21 in quants what colleges should I aim for ?

Hi sonakshi,
This year, you have fallen into an unfortunate category which happens to many students every year. Despite being a good score, you will not be eligible to any IIMs since you do not clear the sectional cut-offs.

IIT-B is out too. IITD also has sectional cut-off of 80%, hence that is out
IIT-kgp does not have sectional and considers entire profile into consideration.
You should apply to IIT-kgp and IIT-kanpur

Apart from that, I hope you have applied for MDI and SPJ. Those two are the best things available for you at this time.
If you have a suitable engineering background, NITIE is the best in the country for a masters in operations. They do not have any sectional cut-offs.
As fallback option, you can apply to IMI and IMT

We have also made a detailed video on the same subject. You can check that out
Colleges to target for 90+ percentile in 2020
I would recommend you to write other exams. PGDBA applications is still open
It is excellent option too
Wish you best of luck:)