Press and hold the Power button until the display shows Loading Startup Options, then release it. This takes you to the Startup Options screen.
At present if you disable System Integrity Protection you will be unable to launch iOS apps. It is unclear as of now if that is the intended behavior.
Currently we use the open source mach_inject project for loading our plugins. Updates will need to be made to this underlying injection system, beyond just re-compiling the code, to support M1 machines.
It is also possible extra protection has been built in but until we get our own M1 machines for testing we don't have much additional info.
This info is relevant for cDock, MacForge, DarkBoot and any of our other products that require modifications to System Integrity Protection in order to function.