Doe the boxes have actual seats?

Yes

Yes, great views

Sound is better on ground floor though.

The seating setup changes from show to show with folding seats (padded) set up in areas like the standing bleachers at the back of the venue (all 3 levels). If you bought a seat, you get a chair, to state the obvious. They probably anticipate seat sales, then open sections of seating as seated sales ramp up.

The seats were very comfortable

Yes each seat in the box is ticketed individually

Party, most boxes only have seats for the first two rows, the third row was standing at the Lumineers concert.