How to exclude Categories from Loop

Dear Folks, i was wondering if you could help me out.

I am aiming for a very simplistic approach to the theme.

I would like to exclude some posts by category of the main loop
and have those appearing on the page “media” instead.

It′s probably very simple, but I don′t seem to be able to figure out how. Is it a query-function? I tried one in my child theme with a page-template for the media page, but no luck.

Here′s the website –> https://www.exzw.de

Greets, leh