Ds lite repair for foster kid

I got this ds lite that gathering dust because it didn’t work. I started watching these videos for fun and I thought I might be able to fix it my self.

The light turns on when plugged in and stays on. The battery seems to be good. (No bulges and was fully charged).

I opened it up and tested all the fuses. I wasn’t able to find anything out of the ordinary so I watched a video and I found out there is a fuse right next to a black box. I tested it and it’s not working. I am bright new at this and I don’t think I’ll be able to change a few so small. Can somebody help me with this? I’m hoping to set it up so my foster kid can play with it.

I have pictures in the link to a video but really not allowed to put them in here.

I just found out it is either L2, or F2 fuse (Count hear the a guy in the video) by the battery prongs