You can set the form's RecordSource to a query name or
even a SQL string if necessary. Of course, if you want to
edit the records it needs to be an updateable query.
If you're just trying to look up something returned by a
query you may want to look at the DLookup() function. You
could set the control source of a text box to something
like...
=DLookup("MyField","MyQuery","[ID]=" & Me!txtMyID)
Good luck.