For help, type “help.”
The issue: Others have made this point before, but it bears repeating. In some styles of English writing, punctuation marks by a quotation mark are put inside the quote. (He said, “Stop.”) In some, they are put outside. (He said, “Stop”.)
The problem with the first style is that the period can be taken as being part of the quote. If this is a command to type into a computer, it has likely been made wrong as the command probably does not include a period. If writing in the first style is converted to the second style, the command will also be made wrong. One possible solution is to rearrange the sentence: Type “help” for help.
This distortion can happen in other ways. ‘Did he say, “Help?”‘ makes the quote into a question which it probably was not.