That does not look like a Winegard, but they all work in a similar manner.
The light means you have 12 volt power to the switch. I attached a diagram for the Winegard to show you how the "guts" are connected and it may be similar to yours (or not).
In the lightening storm you could have fried the power supply or the amp in the antenna (or both) (or neither).
If park cable is available, select CABLE and the light should be OFF. Using the TV scan for channels using the CABLE setting on your TV, (NOT AIR).
If cable is not available, you will need to troubleshoot using the roof antenna. Select "antenna" - LIGHT ON - and rotate the antenna (if yours rotates) to point the white "box" AT the transmission towers. Use a program like www.antennaweb.org
or a phone app like TV TOWERS to locate the direction to point your antenna. (Antenna is like an airplane with VHF elements as the wings and the UHF antenna (inside the white box) as the cockpit. Your intention is to "fly to the towers."
If you are handy with a voltmeter, go up on the roof and remove the COAX from the antenna amp box and (with the green light on) measure for 12 volts DC between the COAX center copper wire and the wire ground shield (the threaded nut is OK).
If you have 12 volts there, make sure the antenna is pointed at the towers (clean any corrosion and reconnect) and go inside to scan again using AIR as the signal source.
If you use www.antennaweb.org
to find your towers the computer screen will look like this (shots from our camp site at MacDill AFB Tampa, FL.
NOTE: the towers ARE NOT in the city! Pointing away from the towers will cause "no signal" errors due to the signals being digital and VERY directional these days.
NOTE: also there can be MANY towers in different directions and you may need to rotate the antenna to the correct heading for the station you want to watch. Your TV may also need to be "re-scanned" to get that particular station.
I normally point to the direction that has the most major network channels during setup and only move it if there is something on the "off" local channel I want to watch. I use TITANTV.com to get channel listings for my camping area.