If you are getting the error "zsh: command not found: virtualenv" it means that the virtualenv package is not installed on your system. To fix this error, you can try installing the virtualenv package using pip.
pip install virtualenv
If you don't have pip installed, you can install it by following the instructions on the pip website: https://pip.pypa.io/en/stable/installing/.
Once you have pip installed, you can use it to install virtualenv by running the command above. After installation, you should be able to use the virtualenv command without getting the "command not found" error.
If you continue to have trouble with this error, it's possible that the virtualenv package is not installed in the correct location on your system. In this case, you can try adding the path to the virtualenv package to your PATH environment variable. This will allow your system to find the virtualenv command and use it.
Here's an example of how you can add the path to virtualenv to your PATH variable:
Replace /path/to/virtualenv with the actual path to the virtualenv package on your system. You can usually find this by running the "which virtualenv" command.
After you have added the path to virtualenv to your PATH variable, try running the virtualenv command again to see if the error has been resolved.