I am very new to Command Line and have been following the Learn The Command Line course. I’m running Mac OS Catalina / Big Sur and both use Z Shell. It’s mentioned at the start of the Configuring The Environment chapter that you might have Z Shell and there would be some differences.
A bit more detail, or a link to more detail, would be helpful. I tried out editing .bash_profile on my own machine but got nowhere, because I needed .zprofile, for example.