Hi, I'm not sure what components you want to do this with: gallery, drop down, etc. But this is possible with a few different components. Here is the demo app I made, the left list shows my "case types" and the right list shows all of the cases that are of that type. You would want users on the left, and all of that user's equipment on the right.
Left list that displays case types has this for the "Items" property.
'Case Types'
Right list that shows related cases has this for the "Items" property.
Filter(Cases, 'Case Type'.'Case Type' = ListBox1.Selected.'Case Type')
You could list users, then display their equipment. You could make another list, or just a label for their department. Replace my example tables with the ones you need (users, contacts, equipment, etc).
Hope this helps you get started with what you need.
