When you have Wappler up and running, start by creating a new project as per Creating a New Local Project.
Then have a look at the tutorial https://www.youtube.com/playlist?list=PLUjqTJN3byC9kK8YZkmGwjo9nrEipl2yb to start experimenting.
I find that learning by example is the easiest way to learn a new product. Any problems can soon be solved by going to https://community.wappler.io/c/docs or by coming here to the forum.