If a question, or set of questions, will not be used in the future, it is generally better to hide the question(s), rather than delete them. If the question is deleted, that also deletes that data from all existing records. A better method is to hide legacy question(s).
There are several methods that can be used to hide question(s), but the simplest is to add branching logic so that the question is not shown unless it already has an answer. This hides it from all future surveys or data entry forms, but makes it easy to see the legacy data on existing records.
The variable name of the question is placed in square brackets. Be sure not use any spaces between the square brackets and the variable name, nor between < and >, nor between the quotes.
[variable_name] <> ""
