Well, every post is separate. So, - If you post something under a comic that you want a response to, you just have to go back to that comic and check the posts.
If you want to start a thread on a particular topic, Click on FORUM, and you will see a list of Master Forum Topics. eg, ;Blog and site links', 'Reading Group', Comic Talk ' 'Blog and site rules'
Find the most appropriate and start your thread there.
It's worth not just looking at the comic books, but going through the posts, there is a tremendous amount of useful and relevant information there.
Also, if you want to bookmark a comic so you can come back and find it easily, underneath the picture of the cover, on the bottom right you will see ,'Add to your comicmarks' Here you can pin the book in your own personal space. When you want to come back to that book, there is black strip at the top of the basic page layout and on it there is a link 'COMICMARKS' click that to go to your personal page.
If you want a good random look at what's on the site, go to the Box top right thats labeled 'Latest Comics' click the downarrow and then click 'The Random 12'
Also, please join in with the Reading Group. I am currently Co-Host. If you don't want to comment on the current choice, please feel free to read and comment on an older choice. Your post will get read and possibly responded to. And there will be another one along in a few weeks.
This is a huge site, a credit to those who have created it and worked on it, and there's a lot to do and see.
Cheers!