These days you should use "pwsh" and not "powershell".

But yes, just start "pwsh" possibly "pwsh -noprofile" and then you get a new powershell inside your powershell.

"exit" will termintate the innermost.

In my tests "Remove-Module" works fine for script type modules. It also works for binary/.net based ones as long as you run it before any invocations of said module ;-) After you are caught with AppDomain .Net limitations.