Hey Sambit.

You can use the link which is given below for downloading previous year question papers on CAT along with the answer keys.

https://www.google.co.in/amp/s/bschool.careers360.com/articles/cat-question-papers%3Famp

You can use the link below to download sample papers.

https://www.google.co.in/amp/s/bschool.careers360.com/articles/cat-sample-paper%3Famp

Best of luck!