Is there a box office to buy tickets for future shows or tickets are on line only?

The box office at the venue is only open during the season. But Ticketmaster, Live Nation sell tickets for the shows.

Yes, but during the winter that location box office is closed, but you can get tickets at the Orpheum box office

Yes

There is a box office but it's closed during the winter. Box Office is Open for Daily Sales Mon-Fri Noon-5pm starting the Tuesday after Memorial day thru the Thursday before Labor Day. The Box Office opens at 3pm Saturday and Sunday on show days only.

I think there's both, but I bought online, so I'm not positive