If your Pi has a keyboad, you can also press F4 in Emulation Station to get to its command shell, and then enter sudo nano /opt/retropie/configs/all/autostart.sh to edit the file. In the editor, press Ctrl+xfollowed yand Enter to leave and save the file (or press n to not save it). You can leave the command shell by entering exitor pressing Ctrl+d.

Finally, you can also use SSH (Secure Shell) to access your Pi. See the Docs about that.

@redbatman based off my experience, the pi 4 is borderline just a tad too slow for n64. No game runs at 100% speed at all times. Your tolerance for minor slow downs will make or break your experience. But it’s Not that the cpu is too slow, just the way n64 emulation works, the bandwidth of the pi is just not there.

Use the image from retropie.org.uk/download and it should work fine, we don't support 3rd party images.