Frustrating trying to install Sonoma after Big Sur fail

I really want to upgrade from Catalina so I can use both Xcode and OpenCV. I could install older versions of Xcode but getting things like Homebrewer, Fink and MacPorts has been a pain. So I thought to upgrade my O.S altogether.

I tried to upgrade it to Big Sur first. I made a post about it this morning. Now I’m trying to install Sonoma, see the error message that occurred. This has been taking me a whole week I really need help with all of this. It’s really frustrating, I just want to get on with my work. Any help appreciated.