Just got my Apple IIc screen, so I was finally able to confirm that the machine (including the disk drive) works!

Does anyone have any useful primers on how to use an Apple II?  I haven't used one since I was in elementary school, and even then it was only to play Oregon trail.

When I turn the machine on, it just says "Check Disk Drive," even if I put a disk in it.  If I have a disk in it before I turn it on, it loads the disk.  Is there a command/button combo to get it to read a disk I insert AFTER I turn it on?

Any list of key combos/commands would be useful and appreciated