[Answered ]-App '\udccd' could not be found. Is it in INSTALLED_APPS?

For some reason your command line managed to pass in a surrogate UTF-16 code unit. The warning message is telling you that one of the app names you passed in to the makemigrations command is not available in INSTALLED_APPS but that Unicode character is clearly not a valid app name.

What happens is that your command prompt produced the extra code unit either before or after the myshop argument, passing it to Python in the sys.argv list.

You need to figure out how your command prompt is passing in extra bytes. Experimenting with import sys;print(sys.argv) should show the extra information that is being passed in. It may be that you are somehow typing it on the command line; you need to get rid of it if you want your command to succeed.