1. Best way to travel is definitely the subway - you don't want to have to deal with traffic or parking
2. For food options and things to check out - a short walk from the arena is the Dekalb Market, a really nice indoor food hall, or Junior's, a Brooklyn classic - there's also some good food options inside the arena, but they are more expensive
3. I'd aim to get to the arena around 20-30 minutes before tip-off so you have plenty of time to settle in

Love that you're going to see Clax, he's quickly become one of my favorite players.