I've tried to install flutter multiple times, and could run flutter doctor once, but after closing the terminal I couldn't. Don't know how I did it, and this keeps coming on the screen.
user@users-MacBook-Pro flutter % export PATH="$PATH: /Users/user/Desktop/flutter/bin"
user/users-MacBook-Pro flutter % flutter --version
zsh: command not found: flutter
user@users-MacBook-Pro flutter %
So I have changed my path, changed the shell to -zsh, because I work with macOS Catalina, but nothing seems to work. What should I do?