No start? I assume from what you wrote that the engine did not crank or turn over??
If the starter is not engaging it could be the starter, but first just turn the key on, apply the parking brake, put the transmission in reverse, and check the backup lamps. If not on you could have a bad neutral safety switch on the transmission.
The next step would be to find to jump the starter to see if it will run. There is a connector on the frame next to air filter. Jump the correct two wires and the starter should crank.