Thanks! The main tip I can give you is to genuinely enjoy making games. As long as you enjoy the process, your games will naturally get better and more polished over time.
The food truck idea is creative, but people buying food are usually not gamers, so it might not get as much engagement as you hope. No harm experimenting though.
My final advice is to make a game that you personally love to play. Not just because you made it, but because you would genuinely enjoy it as a player.