In Konverse the majority of the posts in your app will allow you to add a comment to a post. There may be a few where comments are not allowed, but it is room specific. The ability to comment on a post is determined by your app admin and is unique to each room.
For those posts where you are allowed to add a comment, scroll down to the very end of the original post. Immediately below the Views, Likes, and Comments icons you will see a text area prompting you to "Write a reply ..." Simply tap your screen (if on mobile) or add your cursor to the text area and beging typing! Before you finish, you can also add an attachment to your comment by clicking on the paper clip to the left of the post button.
When you have finished your comment, hit post and your comment will now appear for all to see in the thread of comments associated with that specific post.
New comments alert the original post creator and anyone else who may have commented or subscribed to that particular post.