There is no Orce Forum Post Page to Build

In Page Builder I can find "Forum Home" & "Forum Index", but there is no builder for Posts Pages. How do you add a column to the post pages?

if you are referring to adding topics and threads to your forum, those are done from the manage forum locale on your site.

but you are correct there is not a block builder for adding threads or topics.

The issue is that I can't add any columns on posts pages. If I want to have other posts, advertisements, etc. aside of a post, how can I do that?

You'd have to edit Orca's template files directly. I don't have much experience with this, though, so I can't really be of help.