I’m trying to take the value entered for userid from a start up menu, select an option on the switchboard which is to run a form which asks for a location and a cost center.

I want the form to only have the options available for location associated with the userid which is in a query. Then I want to only have the cost centers available for that userid and the selected location. How do I carry values in variables to add it to a form to restrict the options available?