Okay, well if you have
no running system and are not trying to repair one already installed, then it might be best to start again by completely re-partitioning the SSD as GUID and following the Catalina guide, checking your BIOS settings etc.
If you have a UniBeast 10 installer drive for Catalina it should just work, because it includes Lilu and Whatevergreen kexts to work around the black-screen problem. (Just out of interest, this is a common problem caused by a double-initialisation of a PCs display which makes macOS choose the wrong output. It was originally cured by a Clover setting called
RadeonDeInit, but now the kext method is generally preferred).
As you say you had a working Mojave/Catalina system previously then obviously something has changed. Catalina 10.15.4 does seem to be proving a little tricky for some people at times, so maybe consider going the Mojave (or earlier Catalina) route again until you have a working system you can backup - and then start experimenting?
It's normal for some USB ports to seem "dead" until the OS kicks in and activates them.