This article outlines how box office sales work

Note: Normal Box Office users (who do not have Admin or Manager user roles assigned to them as well) can sign in on the normal log in page (~/login.aspx) and will be taken directly to the Box Office Administration panel. Otherwise, for users who have Admin or Manager user roles assigned to them, once logged in as normal from ~/login.aspx, click Box Office from the links listed:

Once you click Box Office, you will arrive at a drop-down menu.
1.  Select ticket sales from the list.

2.  Select the event you would like to purchase tickets for:

3.  Select the event date and click Find Tickets
4.  Select how many tickets of what group for group ticketing events
5.  For Group Ticketing Events; Box Office staff is able to override default fees such as Sales Tax, Shipping Fees and Service Fees.