My arris router went out after a thunder storm that struck close to me

Sorry, that’s not good.☹️😩

Lightning strikes are deadly to devices like routers and wired phones as the strike kills either with its massive energy passing through frying things or the LEMP pulse though the air kills things.

Time to get a new unit as the damage and cost to try to rebuild the unit will be much more expensive if even possible vs replacing.

Given how close the strike came you need to get someone in to inspect and repair your buildings electrical ground circuit as often these get damaged and look at getting a breaker panel surge protection unit to offer the first line of protection from a power line strike. Then look at getting a few surge units for any wired devices like network gear (Router and Ethernet hubs), TV’s or Radios which have external wired connections or antennas. And lastly make sure all of the buildings outlets have properly wired outlets as often times the third grounding prong is not wired or the needed wire is missing.