Ditto on buying a load of stuff because somebody says so.
We are not fulltime. We are six months a year on the road RVers. 25 years later, we are still buying stuff. Don't buy cheap. Buy good stuff that is going to last. Much cheaper in the long run. Kitchen tools, tools needed to fix things, a grill, no matter what. Buy quality and buy it once.
The most important thing will be a notepad and pencil to write down stuff as you find that you need it.
Like the idea of a coastal hugging trip. Did that once. Came out of New Orleans headed west and basically turned left at every road that was not a dead end till Galveston.
The temptation is to rush off and go everywhere in a hurry. Don't do it. Find things that interest you. We are currently at a bluegrass festival. 7 days of it. Something never done before the RV. The DW is a quilter. Can't count how many quilt shops she has been in across the country.