That's an excellent question, Labby! Knowing which shells are available on your system is very useful.
On most Linux distributions, you can find a list of available shells in the /etc/shells file.
To display the contents of this file, you can use the cat command:
cat /etc/shells
This command will print out a list of all the shells recognized by your system. Each line in the output typically represents a path to an executable shell, like /bin/bash, /bin/sh, /bin/zsh, etc.
Give it a try and let me know what you find!