MacBook Air (13-inch, Mid 2012)

Those should be able to run in Catalina 10.15.7 unless you have need to use

32-bit third party drivers; or your older printer etc won't do without those.

• Go64: Check Your Apps and Prepare for a 64-bit World

https://www.stclairsoft.com/Go64/

One of the details with upgrade to a newer technology.

For old/new macOS upgrades and compatibility, see:

• How to get old versions of macOS - Apple Support

https://support.apple.com/en-us/HT211683

Make backups; too easy to upgrade and then have no

path to return to something older, that may just work.

Time Machine is means to make backups of your Mac.