You can organise posts into category. Each post can be assigned to multiple categories. First you have to create a category. Open Posts > Categories. You will see list of current categories you have. To add new one. Enter Category name, slug and click “Add New Category” button.
Assign Post to Categories
Now when you create a blog post. Look at categories option box, select categories you want to assign and save changes.
Setting up Category Page
When you created a category. WordPress actually creates category for you. To add a category archive to one of your menus, go to “Appearance > Menus” in the WordPress admin. Look for the section labeled “Categories.” Then, select the categories you want and add them to your menu.
You can customize category page layout. Go to Appearance > Customize > Blog > Layout > Category Page Layout and select layout you want then save changes.
Posts per page
From your admin sidebar, open Settings > Reading. Then adjust number of “Blog pages show at most”. Once you finish, click “Save Changes”.