Posts are one of the 2 default types of content you can create in WordPress. The other type is Pages.
Posts are used for adding Blog Posts to your website. These can be news updates, SEO articles, Content Marketing pieces, etc. Posts are different to Pages in that they include Categories, Tags, Post Dates and Comments.

Adding Posts
To Add a new Post, first Login to your website.
Basic
- Go to Posts in the left Sidebar
- Click Add New
- Give your Post a Title
- Add your content
- Give your Post a Featured Image – this will show in the list of Posts, at the top of your Post and it helps with SEO and Social Sharing.
- Allocate at least 1 Category.
- Click Publish (if you want your Post to be visible by the public immediately), Save Draft (if you would like to save progress and continue working on this Post later), or Schedule (by setting a future date for its Post to go Live)
Advanced
8. Set the SEO Title and Meta Description in Yoast