Counting number of choices in Multiple selection


HI Ragic Team,
I have to count the number of choices in multiple selection. For example The engineer can scan barcode of machinery to choose but he has to recheck how many items are checked/scanned. So could you direct me as we had formula or how can I do that?


As we are not quite sure about what you meant, do you mind sharing with us an example and screenshots of it for us to refer to?