iMac 2010 27in OS High Sierra

There aren't any newer versions of macOS that will run on that computer.

There are some applications that might extend the useful life of the computer, but even there, you may be dealing with old versions. E.g.,

• You can run Firefox 115 ESR on High Sierra – but not the current version of Firefox.
• You can run LibreOffice – but only old, unsupported versions. The archives aren't organized too well as far as making it easy to determine the most recent version that is compatible with High Sierra.

No newer macOS versions are compatible with that iMac model.

(250140)

You need a new Mac if you want anything later than High Sierra.

Those larger screens with built-in DVD drives are nice. I used to have one. I finally decided to get a newer computer so I could run the current versions of tax software and update my will. Sure as death and taxes, computers will become obsolete. As newer hardware is developed, a newer OS is required, and they can't continue to support older hardware indefinitely.

Might be able to set up a BootCamp partition and run more a current version of Windows or linux maybe.

It's perfectly good running up to High Sierra.