What does waik-in mean in the hotel guest file form?

If it refers to the hotel industry, it is not waik-in, but walk-in, which refers to the guests who come to check in without booking in advance, referred to as "individual guests don't book", which corresponds to check in.

Come without an appointment

[English] [? W? :k？ In] [America] [? W? k？ Make an appointment, make an appointment; Make an appointment Come without an appointment;