HELP! New Cr3 files need to convert but running OS Sierra 10.12.6

[malamamysoul]

Aloha! I feel so lost. I cannot afford to upgrade or even update because I know I will lose files and LR catalogs and I need to find a DNG convertor for CR3 files that will work on my OS Sierra 10.12.6 - can anyone help me? Mahalo for trying! 

[Lumigraphics]

If you can't upgrade past OS X 10.12, you have a LOT older computer. At some point you no longer have any support which is what you are seeing. Your best bet is to get a newer computer. A used Mac that will run the current Monterey should be available for maybe US$3-400.

I'm not sure if Canon Digital Photo Professional will run on your system either but that's your other alternative.