@jpca999 did you copy-paste that code from the internet? Those quote marks don't look quite right around ionic serve -port 81 (try retyping the quote characters, you should expect to see syntax highlighting). See this page for more info.

Closing this, because this has nothing to do with ShellJS.

No I don't did not copy paste the code

@jpca999 Why are you intentionally typing strange quote characters? Specifically, why are you typing U+2018 (LEFT SINGLE QUOTATION MARK) and U+2019 (RIGHT SINGLE QUOTATION MARK)? Those are not valid quote characters in JavaScript, you need to use U+0027 (APOSTROPHE)