Charging batteries with a 2000w generator

[Dobie dogs]

I have question. We travel to Florida taking two days to get to our destination. So I’m wondering is a 2000 w genny enough to charge the batteries while running the heat for a day until we get to the warmer climates.
We usually don’t boondock at all except for traveling to Florida.
We have two 100 amp batteries and they charge while traveling but my question is should I use an adapter from 30 to 50 amp while stopped and use the onboard charging system or charge the batteries using a battery charger. I’m thinking just plug in using the adapter. so we don’t run down the batteries while using propane for heat and a light or two. The residential fridge doesn’t use much. I have a battery monitor and about six hours after stopping the low battery alarm will start sounding off and we are out of power.
What are your thoughts
Charge the batteries using a charger or hookup with an adapter?
I hope I wasn’t too winded but hope you have enough info.

Thanks in advance, Bob