I cant see my categories

So I have bought the PC Builder for my ecommerce website.

I have found a tutorial https://www.youtube.com/watch?v=kf6pcGfx4fo&ab_channel=VillaTheme which seems to be straightforward however, in my attached image (LEFT) you can see the options I get to choose categories which are not showing any sub categories and other categories at all (shown in right image).

I have a lot of categories Components->CPU, Components->Casing, and so on..

Is this the start and end of this so called famous plugin or am I doing something wrong here?

Would appreciate your help

Regards.