Using iMac as monitor for Mac Studio
To use my 2013 iMac as a monitor for my Mac Studio, do I have to downgrade my operating system from Catalina to High Sierra?
Question marked as
That will not work, because M1 Mac’s can not be downgraded and they do not support Target Display Mode.
carefully read > Use your iMac as a display with target display mode - Apple Support
If you get an M1 Mac Studio or M1 Mac mini, then you will also need an external display.
see > Connect a display to Mac Studio - Apple Support
and > Connect a display to Mac mini - Apple Support