Will transportation be provided to and from the hotel to the venue?
No, you will be responsible for transportation to your desired destination. I suggest Uber/Lyft, as it is the cheapest option, espeically if you can catch a ride with other wedding guests.
which airport should I fly into?
Denver international airport (DIA) is the airport you will want to use. It is about 30 minutes away from the venue, and it supplies most major airlines (spirit, frontier, delta, american, southwest, united, etc..)