To be seen on Google search,do I have to create a new file(page) for each user post or is it enough to retrieve from database?

I am creating a forum website from scratch that every member can create posts.When a member creates a post,I insert it to the database and when you click the post's heading,I retrieve it from database and the URL is like : http://bit.ly/2V0cNrs But when I check the other forum websites,it is like : http://bit.ly/2GCT1bK The question is,if I keep doing this way(retrieving from database),are the posts invisible on google search and will it effect my SEO badly?If it is invisible,what should I do to retrieve it like other forums do?(like opening a file when user creates posts etc...) By the way,I am using php