It’s often remarkably easy to hide things.
Get used to the browser’s inspector.
In the browser on desktop, right-click somewhere on the element you want to hide, select “inspect”.
This will open the developer tools and the html view.
Find the outermost div you want to hide, remember its class.
Then simply put this into a Theme Component:
.my-class {
display: none
}
In this case the class I believe is called topic-navigation
this might hide too much as you lose all these controls, but experiment.
you can preview the effect by modifying the CSS in the middle box area, get rid of changes you’ve made by refreshing the page.
Learning these basic skills avoids a lot of noise on Meta.