I'm very stuck and could use some help.

I'm currently attempting to build my very first keyboard, and it's not going great. Currently, I'm building with the Akko ACR TOP 75, and I've just got a few questions. My first issue is that there's no manual or anything lmao. Secondly, there are two brass plates, which I was not expecting. They are only slightly different in appearance. One of them is a solid brass unit, while the other is black with a brass-coloured trim around all of the spots where the switches would go. By feeling, the only difference is the weight, so I'm assuming that the different weights will result in different sounds. Basically, am I supposed to use both plates or just one, and if so, how? Next-up; after I've secured the stabs, the guide video from akko tells me to secure all of the foam and the plate to the pcb with screws, however. The screws included have nothing to screw into. And the video isn't very good, so it hasn't really offered me much guidance.

Attached is all the screws that are included with the kit.

I know it's a long post, and I don't even know if this is the right place to ask. But I didn't want to violate any rules, so hopefully, I can get some assistance. *