Couple things. That generator will probably have a couple 120v 20a plugs. It also has a 30amp rv plug. So 30amps at 120v =3600w. That's the most you are going to pull using a single cord.
Your peak running amps on gas on that model is only 30amps any how.
You'll need an RV extension cord when you put an inlet in for your transfer switch like this one. It's graded for 40amp so it will let you use the extra umph for startup watts if you need it.
https://www.amazon.com/Mophorn-Durable-Premium-Extension-Motorhome/dp/B06X9NGN23
Until then you are better off with 2 20 extension cords. This one will give you 3 outlets but again capped at 20amps.
https://www.amazon.com/20-Extension-Triple-extension-T-Blade/dp/B0819C73N3