To "display" data from another table, you can use DLookup or the Column(x) of a combo box.
Data "looked up" from the table should NOT be stored again in another table unless it is from a table that is specifically designed to provide "lookup" data.
DLookup("FirstName","tblEmployees","[EmpID] = Forms!frmFormYouAreOn![EmpID]")
Me.UnboundTextBoxName = Me.ComboBoxName.Column(1)