You picked a difficult system to start with, as Amiga emulation is a little difficult when you know nothing. I will try to offer some very basic guidance, although the only real way is to Google heavily and read related guides. Or find a friend who is already familiar with the concepts to give you a kickstart.
By "TOSEC Amiga" I presume you mean that you downloaded a collection of .zip or .7z files that contain .adf files. These are images of floppy discs that the original Amiga hardware used and contain Amiga code. They will not contain any PC executable files. If you don't have these zips, you can't play any Amiga games.
To run Amiga zips on your PC. the executable you need is WinUAE. However, before anything happens you need to configure it correctly. This step is difficult, you need a basic grasp of how the Amiga worked. I can't go into details here, would take me hours. There's a guide that looks decent at a quick glance here: http://www.tweakguides.com/Amiga_1.html
. It's from 2011 so there may be some changes in the current WinUAE version, but the basic operation should be the same. I am sure there are more to be found by Googling for something like "how to configure WinUAE" and browsing through the results.
RomVault and the DAT pack are useful to manage your files collection and given them proper filenames, but I think you should probably first learn how to use the emulator!
For screenshots, manuals and the like: this is not something supported by the basic WinUAE setup. Or most other emulators for that matter. If you want this functionality, usually the easiest way to do it is other programs called "Front End" that sit between the emulator and you and display all these nice things (which again you need to find and download separately). A nice Frontend is Launchbox: https://www.launchbox-app.com/
. There are many more of them and I have never looked into much details on this field, so I can't say for sure which one is the best. However, I would recommend that you become more familiar with the basic operation of a single emulator and all the terminology used before diving deeper in. Once you are able to easily start a given game, you can start thinking about getting manuals and screenshots, as this is secondary functionality.
In any case, I think you need to start reading. Don't try to get everything in one go, it takes patience and time to understand all. I had to go through this process myself when I started the hobby. Hope I have helped a little.