decide among (someone or something)

To choose someone or something from three or more options. We've had so many good candidates for the job that I'm having a very hard time deciding among them. How am I supposed to decide among so many tantalizing dessert options? They all sound delicious! There's so many places we could go for vacation that it's hard to decide among them.

decide between (someone or something)

To choose someone or something when given two options. Holly and Jack are both such good candidates for the job that I'm having a hard time deciding between them. How am I supposed to decide between tiramisu and cheesecake? They both sound delicious! We're trying to decide between the mountains and the beach for our vacation.