How do I upgrade macOS X 10.6.8 to a newer system?

That would depend on exactly what model / year of Mac you have. You can find the model / year in the Apple Menu ➜ About This Mac.

Being at 10.6.8 Snow Leopard, means it's pretty old, so there may not be much to upgrade to though.

Phil0124 wrote:

That would depend on exactly what model / year of Mac you have.

I see that the OP has not been back to answer this question.

Being at 10.6.8 Snow Leopard, means it's pretty old, so there may not be much to upgrade to though.

High Sierra at best.

My 2011 iMac came originally with 10.6.8 but can officially upgrade to 10.13.6 - and there is a HUGE difference between those two OS , even though 10.13 is now pretty old. Much of my software still runs in 10.13, and you can browse either using Firefox 115 ESR (soon to be not supported by Mozilla) or Firefox Dynasty, a GitHub project based on Firefox 134.

👍