How to create Joomla category

At first Login from your Site Administrator.

Then go Content => Category Manager => Add new category

Explain

1. Title = Give any title name.
2. Alias = Leave this blank & Joomla will fill in a default value from the title. This value will depend on SEO(search engine optimization) setting.
3. Parent = select a parent category from the list.
4. Status = Set publication status from the list. If the article is not published, it will not be shown to your visitors.
5. Access = the access level allowed to view this item to another.
6. Permissions = Manage the permission settings for the user groups below. See notes at the bottom.
7. Language = Assign language in this category.
8. Then click save & close.