Well, I go to try of resolve some doubts:
1. The floppy disk, it works fine? because you have use the floppy disk for Amiga OS 1.3.
2. You can use a external controller, (I used M-TEC) where you can to install three important things for one Amiga 500, the Hard Disk of 100-200-300 MB, extra memory 2-4 MB and the third thing more important the ROM 2.0 or best 2.01 with it you can use Amiga OS 2.0-2.1 and it give you access to use the HD with the OS installed, and here you can install the WHLoad.
3. Important the mainboard revision, because the last boards have the FatAgnus with addressing of 2MB of chip memory and other things that I don't remember.
4. There are classic games that you can install without the WHLoad, (fews)
5. And very important the general state of your Amiga, mainboard, powersuply, keyboard, and floppy disk if the original is bad you have find one PC floppy but the single density 720 KB not the 1MB.
And for finish, is very difficult to find one controller, you can search for ebay and second hand, the Rom there are availables, 2.01, 2.0, even 3.0 for you can run the Amiga OS 3.0 in your A500, the memory now I don't know, the floppy drives, well, also is difficult find new Amiga drives, because are selling PC drives modified as true Amiga drives, but when you insert one disk, here is the problem, the Amiga doesn't run automatically, old single drives from PC, well, the second hand, and power supplies I think that there are in Amigashops.
I hope help you, in your Amiga experience.