Can I use a regular extension cord for my generator?

No, you cannot use a standard orange extension cord for a generator — that is a fire hazard. Generator cords are built for continuous high-amperage loads; a typical 16-gauge household cord can overheat, drop voltage, and melt its insulation. For a 30-amp generator up to 50 feet away, use 10-gauge wire; for 50-100 feet, use 8-gauge.