Why won't my iMac update anymore?

abdurrahiim wrote:

For some reason I can't update my iMac to the latest version.

A - Update as in update to latest stable version of Big Sur version 11.6.8 ?

A - Or upGrade as in upGrade to Monterey macOS 12.5 ?

A - Update to Big Sur 11.6.8 - what does Terminal command below show in the Output ?

 softwareupdate --list-full-installers

The above will only search for Full Versions of updates or upGraded this computer qualifies to run

It may be too old for Monterey. You need a iMac introduced in late 2015 or later.