I believe what you need is the wp_list_categories()
function. You would need to do something like this;
wp_list_categories( array(
'orderby' => 'name',
'show_count' => true,
'exclude' => array( 10 )
) );
This will list all the available post categories ordered by title. You can have a look at the docs for this to find a list of all the parameters you can use.