You may have installed ZSH and every-time you open your terminal, it opens BASH by default.

How do you set your default shell to open as ZSH?

It’s easy, you can just use the change shell command:

chsh -s $(which zsh)

After running this, close and reopen your terminal for the change to take effect. You can verify it worked by running echo $SHELL — it should show /bin/zsh or wherever your zsh binary lives.

Earlier post on cli goes deeper.

If you get a “chsh: /usr/local/bin/zsh: non-standard shell” error, you need to add the zsh path to /etc/shells first. On macOS, zsh has been the default shell since Catalina, but on Linux you’ll almost always need to set it manually after installing. Oh-My-Zsh is a popular framework to set up on top of zsh if you want themes and plugins out of the box.