This looks to be a direct vent power vent gas water heater. These generally have electronic ignition which is automatic. There is a sequence of things that need to happen before the burner will ignite. Have you tried disconnection power for a minute then returning the power? Also does the inducer fan operate correctly?
No lights means there is no power, or the on' off switch is off. Here is the guide. If you do have power to the water heater, then you will need a new controller.
Ok I will look for it. Just make sure your heater is going through the sequence. The inducer blower should come on first, then the pilot should light with an electronic spark, then the burner should come on. If the blower is not coming on, then there may not be power to the unit or there may be a problem with the fan. If there is not proof that the fan is operating, then the ignition sequence will not start. But there is no way to manually light this water heater.