The answer to this question depends on if you're playing in a 9-hole or 18-hole event.
If you are staring your event on the 10th hole, and everyone tees of from that hole, turn on Shotgun Start from the Event Tab.
In the Golfers Tab, set every golfer's start hole to 10.
Now, when a golfer opens the scorecard and clicks Tee Off, they'll be taken to the 10th hole and finish on the 9th hole.
Unfortunately, right now, all 9 hole events use hole numbers 1-9. It is an issue our development team is working on and will hopefully publish an update soon.