Trouble repairing Mac disk in Mac Utility

Hello,

I need some help repairing my Mac disk.

Tonight when I restarted my Mac (an old one from 9 years ago) the file icon with a question mark showed up. I googled and discovered that it meant my disk needed repairing.

I went through the suggested steps but got stuck when I tried first aid. See picture below. I clicked on the Mac OS X Base System and the first aid box appears (beside it is erase and restore up top) and there is a white box where I think my disks are supposed to appear and then the verify disk permissions and repair disk permissions and verify disk and repair disk buttons are all greyed out. I’m assuming there needs to be files in that white box that I can ‘perform’ first aid on.

Theres also no sidebar to select ‘show all devices’ from (as it said to do in instructions) I think because it’s an old version.

Any ideas what’s wrong? Or if I’m missing something/a step?

Thanks