Hi,
We have build a Reservation Desk App, using the below SharePoint lists:
1 - Reservation Desk (with desk number: desk 1, desk 2, desk 3...)
2 - Reservation Details ( with all the reservations made)
What we want is that, when a user is selecting a day, in the reservation screen, the desk already occupied to appear with red and do not allow to check the box.
Could you please help us?

We don't want to use filter, to appear only the available desks. We need this format but with the above conditions.
Thank you all!