Thanks for your reply...

Search engines treat each domain as a separate site. Each domain has its own separate file. On the main domain in robots.txt, you do not need to specify settings for the subdomain.

My website has a few subdomains, but I need to disallow it from google. After a long review, I have found that all subdomains have their own robots.txt file and from there you need to disallow the boot to index that page from google.

But my main concern is shall I disallow that subdomain from my main website robots.txt file

Subdomain - https://kinsta.jigsawacademy.com/robots.txt
Main domain - https://www.jigsawacademy.com/robots.txt