Use a late 2012 27" iMac as monitor for 2017 MacBook Air?
My late 2012 iMac is running Catalina, my 2017 MacBook Air is running Monterey. Both are up to date versions. Talked to 2 different Apple techs and got 2 different stories about if I can use the iMac as a monitor for the MacBook Air. One suggested all I need is a USB C to USB adapter, then a USB cable. The other lead me through a long involved discussion about macOS compatibility, and finally needing a Thunderbolt 2 cable to connect the 2 devices.
Are either or none of the above going to get the job done? Thanks for any help you can provide.