representation of different elements /blocks at different pages


could your please show me, how can I define which content/blocks  are to be visible at the homepage or in the subpages.

I have installed/assined my own theme with demodaten. I can override base.html.twig and other template files.

But I do not understand, why the homepage shows me the filtering and the pruduct list and no sidebar menu, for example. Which file defines this?

The answer is  different layouts. Those one can  in backend  create and  to different categories assign.