Plane won't move forward after "I" key

[Baer]

Ok, take off really stumps me;

1. Open fuel ****
2. prop pitch 100%
3. magneto M1 (already set)
4. radiator open 50%
5. trim oil cooler
6. Flaps 20%
7. Throttle 10%

Hit "I" switch to start engine.

Trouble is I do that and once engine starts I push throtle forward but the plane doesn't move. Brakes engaged? What key is brakes?

Regards.
Baer