Any system running Catalina should have SIP disabled. The Unibeast Video has a demo of that process via Terminal.
csrutil disable and a reboot will do it. Required to make the Unibeast USB so just do it now and leave it disabled till that's complete. Also note that with your 1080 gfx card you can only go as far as High Sierra, no Catalina drivers for it.
Your Mac must have at least an Intel Core 2 Duo processor and be able to run older versions of Mac OS X and use Unibeast to create your installer. If you would like to buy, borrow or rent a used Mac mini to create your installer, the 2010 models are the best choice. They all have a Core 2 Duo...
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