Storm outages from nor'easters, summer thunderstorms, and the occasional tropical system are a fact of life in Delaware. There are two common ways to keep power on.
Portable generator + inlet and interlock
An electrician installs an exterior power inlet and either a listed interlock kit on your panel or a manual transfer switch. You plug the generator in with a proper cord and choose which circuits to run. This is the budget option, and it's the safe way to connect a portable generator.
Never backfeed through a dryer outlet with a "suicide cord." It can electrocute utility line workers and neighbors and can start fires. And never run a generator in a garage or near windows; carbon monoxide kills.
Whole-home standby generator
A permanently installed, natural gas or propane unit with an automatic transfer switch that starts on its own within seconds of an outage. It involves an electrician, a gas fitter or plumber for the fuel line, a concrete or composite pad, setbacks from windows and property lines per the manufacturer and local code, permits, and often HOA approval.
Sizing
Sizing depends on what you want to run: essentials only (fridge, sump pump, furnace blower, some lights and outlets) or the whole house including central AC. A load calculation is the starting point.