Add Sidebar to Forum

I cant code, but I can follow instructions.
How do I add Sidebars in the forum Page?
I have added them in the Widgets, but I still get a full page with no sidebar when I view the page

Ive tried plugins and they dont work

Any directions will be helpful…
I would really like to do it myself, so I can learn how to do things, but I just need some directions 🙂

Great Theme