A prolonged power outage can be inconvenient, costly, and (possibly) dangerous. Food in refrigerators and freezers can spoil. Loss of heat can be uncomfortable at best and deadly in the worst case. If critical medical equipment cannot operate then and outage could be deadly. Keep in mind that power outages often happen due to severe weather, extreme cold, overburdened electrical grids, etc. You can protect yourself and your home in the event of a power outage.
Power outages often happen in the winter during storms or cold weather. Storms, ice, snow, and accidents can cause damage to power lines or power stations. Even if you have gas heat you probably need electricity to run the NVAC system. Be sure to have sleeping bags and/or blankets that can keep you warm if the house temperature falls. If the outage last for several days then the temperature inside the house may go down to the temperature outside the house (or close to it). You may be able to use propane heaters indoors but be sure to only use appliances rated for indoor use. Also note that these indoor heaters still require venting.
A generator can supply electrical power to your home when the power fails. Generators normally connect to your electrical breaker box. The power flows from then generators, into the breaker box, and then to circuits in the house. You must install a generator connection properly. An incorrect installation could cause injury to death to utility workers. Be sure to get an electrical permit and inspection when installing a generator.