I'm really sorry, but no way to do this. 

In the "stoner discussions" section in simplified layout, you can see that it does not show the sub-sub forums. 

In that section, there is news and politics, podcast and videos, but they do not show on the front end. 

I would like the threaded layout to do the same thing. I don't want to hide all of the sections, just the sub-sub forums. 

Then if someone clicks on "Equipment" for example, they will then see the sub forums when they are in that section of the forum. Rather than seeing "grow Tents, " Lighting" on the front page.

I hope this help explain what i mean :) 

or example, I want "equipment" to show on the front, but not , "lighting". Guides being the category, equipment being the forum, and lighting being the sub forum. 

I want to be able to hide lighting and other sub forums on the front end. 

Please try the solution provided by Astghik and Elvina in this support topic: https://gvectors.com/forum/general-questions/is-there-a-way-to-hide-pinned-posts-in-this-layout/#post-21199

I'm sorry but there is no way to do that. The only way is list all forums with one column with 100% width. But you can't order them from top to bottom and do that with two columns.

I have attached a pic, I hope it helps. I only want to show the main sections there, i dont want to hide them all as i like the main sections to be viewable. But having them all there is too much. 

Just main forums would be better. 

Also, the forum are displayed left to right on desktop, but show and downwards on mobile. So its difficult to put them in a order as they layout changes in different devices, how do i fix this? 

Please leave some screenshot. What sub-forum you mean? wpForo has a toggle to hide thread layout forums. It can be closed by default.  read the documentation: https://wpforo.com/docs/root/categories-and-forums/forum-layouts/threaded-layout/