You can create your posts via your admin by using the Add New link under Posts menu. If you are not familiar the posts of WordPress you may want to check this page for further reading https://codex.wordpress.org/Writing_Posts
The theme comes with six different post format that allows you create a different kind of posts. You can change your post’s format by using the Post Formats section in a single post add/edit screen. Once you click a format option, it’s options will be appeared as the second section below it.