Categories
View Dashboard > Categories
You can select a category for a post from the post editor page.
Categories on Home page
You can add categories section on your blog's homepage.
How to configure
Visit View Dashboard > Settings > Advanced section
Note
If a post has no category assigned then the first tag of the post is displayed below the post title on the homepage.
Exclude posts of certain categories from homepage
You can select certain categories to be excluded, then the posts of those categories will not be displayed on the homepage but they will be available as individual posts on their specific urls.
How to configure
Visit View Dashboard > Settings > Advanced section