What do I get with a Module?

I'm thinking of running a Pathfinders 2e game on Roll20. The adventure path I'm thinking of using - Extinction Curse - comes with some prebuilt modules for each part. I'm curious what actually comes with the module. It's pretty clear that tokens, maps, and that sort of stuff is included. But what about the adventure itself. Will I need to purchase the adventure path from Paizo to actually know what the story is, or is that included in the module? Thanks

Generally, a module on Roll20 consists of the maps, tokens, handouts, monsters, and NPCs required to run the adventure.  There will be handouts which give you all the wording of the printed module, usually broken down by chapter/section/segment depending upon who does the conversion. As a DM, I find it useful to have a pdf or hard copy of the module, but it is not really necessary.

The Show Must Go On (AP 1) is the module and should be the base if you plan to run the complete AP as the others (AP 2-6) are addons. Modules can not be added to existing games but addons can be.