Upgrade from macOS High Sierra v10.13.6
I have a iMac (27-inch, Mid 2011) with 24GB Mem, Graphics with AMD Radeon HD 6970M 1024 MB and currently need to update the OS to a newer version in order to access certain apps. I cannot install macOS Mojave nor Big Sur any tips or suggestions to help with a work-around? Thx
iMac Pro