If you’ve done an OEM unlock, you effectively already have root access to the device. You could boot a custom recovery right now and modify any system file.
“Rooting” just means using this privilege you already have in order to install a tool into the OS such that you can make use of this privilege while the regular OS is booted.
Go install Magisk and do the safetynet dance. It’s a whole thing but should give you a “clean” device from the perspective of unprivileged apps. It’s stupid that you have to do this but here we are.