Tickets Go on Sale for UIL Football State Championships at AT&T Stadium

My understanding is that if you show up on site they may not have a ticket window open, but you can buy them online even then.
My wife is trying to buy our tickets on line. It's asking what gate we want to enter. She's asking me who's Home/Away? SHS/MC. Does anyone know?
Gate doesn't matter but motley co is away
Thanks. I thought I remembered from 17/18 going to only one (multiple station) available ticket booth near one end zone. You went right on entering for one team or left around the end zone and up the side for the other. Maybe there was another entrance open on the other side. IDK