In the first (training) mission this will be your second objective, directly after destroying the radar array used in "Without Warning". Directly after destroying the array and reporting your progress to your CO, you will be given the option (and on screen guide) regarding calling in strikes. Do so after targeting the village, select bombardment, (or whichever dispersion pattern you wish), and finally Fire for Effect, this will call in the strike on your reticules target.
Notes:
- You will hit "Y" to enter bombardment targeting mode, instead of "RB"
- Make sure you have your target lined up (generally) before before saying "Fire for Effect"