See also:
If the Mac is not your main machine, I’d install rEFInd. Check, if the VMX bit is set in EFI.
Details here:
I have a limit number of massages i can post, but refeind appear more options, i installed Debian unstable and it worked normally, the vmx bit working, but i still cant install qubes… Ah, i installed refind btw, but still no luck 
What is your EFI version? Could you start EFI-Shell? And just out of curiosity: is Mac OS installed?
I installed Opensuse Tumbleweed, and mac os isnt installed, and what is the efi-shell?
And the firmware of the mac is the most recent
Have you tried with a single SATA drive attached? NVMe in particular is a beast in its own right.
Regarding the shell, see the “showtools” parameter. You can enhance the boot environment:
https://rodsbooks.com/refind/installing.html#addons
It gives you some options for early boot parameters (to play with and to find out, what’s going on).
For more hints look here:
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