bash to zsh

I am following this guide https://gorails.com/setup/osx/10.15-catalina to setup a Ruby on Rails dev env on my MacBook Pro. I was prompted to change the bash shell to the zsh shell. In the guide mentioned you show the ~/.bash_profile. Should it be changed to the ~/.zsh_profile?
My system was already a useable dev env before I upgraded to the Catalina OS.

I'm confused as a consequence. Can anyone offer guidance?

Oh yeah! I forgot about that change recently for Catalina. You probably want to use ~/.zshrc instead now.