Suppose I write a long article and display products in one post but it is too long so I want to cut it and continue the next page in the same post? Can I do that in wordpress? I want to display many products so I want to build pages with in a post. One post but there is a navigation numbers like 1 2 3 -- like 3 page in one Post? How do I do that?
You can use the WordPress"nextpage" tag:
You just drop this into the HTML of your WordPress page wherever you want to break it up.
I think your theme must support this tag in order to handle the pagination - on my site I have page "previous/next" links hidden, but most themes probably support this out of the box.