setting up being an administrator on a new mac pro

How many macOS user accounts are on this laptop (admin or standard)? I've seen Macs fail to authenticate in Recovery Mode when multiple user accounts exist.

If you only have a single user account, then try creating a new admin user account to see if that will allow Recovery Mode to authentic as that user instead.

If you are trying to lower the macOS security settings from Recovery Mode, then that is really dangerous. You should be looking at other software to use that does not require you to lower the Mac's security settings. You should never have to lower any macOS security in order to run a third party app. The only security setting I would ever lower would be to allow booting from a USB drive since that can be very useful if something goes wrong with a Mac. A few years ago a simple Google Chrome update prevented Macs from booting for those users who had disabled SIP on their Macs:

https://arstechnica.com/information-technology/2019/09/no-it-wasnt-a-virus-it-was-chrome-that-stopped-macs-from-booting/