When I insert in Terminal
brew install --cask 1password/tap/1password-cli
the terminal answers with
Last login: Sun Aug 6 13:17:09 on ttys003
brew install --cask 1password/tap/1password-cli
ks@MacBook-Pro-von-Klaus ~ % brew install --cask 1password/tap/1password-cli
zsh: command not found: brew
ks@MacBook-Pro-von-Klaus ~ %