In Catalina Apple has changed the write permission of system partition. By default its read only. You need to first enable write permission then install kext in Library/Extensions. Lastly don't forget to clear kext cache after kext installation. For more info check this post, specially "I can't...
You need to carefully read @CaseySJ 's wonderful solution.
Maybe you can try ASRock B360M-itx/ac patch in the spoiler.
Did you install EmuVariableUefi-64.efi on EFI/CLOVER/drivers64UEFI yet? If not then intall it and clear NVRAM and Kext Cache using Mac Optimizer 2.4 (google it) or use nvram -c (At clover boot screen select shell icon, type in the terminal).
How to check nvram:
Why did you installed AirportBrcmFixup and all Brcm related kexts? Do you have any PCIE WIFI-Bluetooth adapter installed in your machine?
I also asked you to delete all files (1-5) not only the first one.
And where did you installed all kexts?
Go to /Library/Preferences/SystemConfiguration/ take backup of these files and delete:
Restart and check. Apple will recreate...
Looks like you need to add "headless platform id" if you want both discrete & integrated graphics work together. Check out this link :
If app store login doesn't work, then you can't download the app which is only available in app store unless you copy the app from other machine and put in your Applications folder manually. By the way, though I forget to update about it but right now my app store login works.