Add categories to autocomplete box

Hi guys ,
Im trying to set my querie suggestion index for my project so I can add categories to
autocomplete searchbox.
I already have my posts_index that represents my articles for sail.
This is a document example

{
  "title": "Bici",
  "country_code": "AR",
  "description": "vendo todo",
  "tags": [],
  "price": 0,
  "negotiable": null,
  "contact_name": "Leostereo",
  "created_at": "2022-02-03T12:41:22.000000Z",
  "created_at_str": "Feb 3, 2022",
  "updated_at": "2022-02-03T12:41:22.000000Z",
  "url": "http://172.30.200.117/bici/144",
  "category": "Tools & Accessories",
  "parent_category": "Beauty & Well being",
}

Then I according to this do:

click on Query Suggestions on the left side → new Querie Suggestion Index.
I used the default names , so it begin building the “posts_index_query_suggestions”
First question:
When it finished building the index , I have 2 records , with no any related data.
Why there are 2 records ?? what are the based on?
I can also view those options bellow my autocomplete box , but they have no sense for me.

Then going inside the posts_index_query_suggestions , I scroll down to categories.
chick → Edit Categories and add the “category” attribute wich I marked as faceting
on my posts_index as filter_only.

Then , when trying to implement this:

const appId = 'latency';
const apiKey = '6be0576ff61c053d5f9a3225e2a90f76';
const searchClient = algoliasearch(appId, apiKey);


const querySuggestionsPlugin = createQuerySuggestionsPlugin({
  searchClient,
  indexName: 'instant_search_demo_query_suggestions',
  getSearchParams({ state }) {
    return { hitsPerPage: state.query ? 5 : 10 };
  },
  categoryAttribute: [
    'instant_search',
    'facets',
    'exact_matches',
    'categories',
  ],
  itemsWithCategories: 2,
  categoriesPerItem: 2,
});

autocomplete({
  container: '#autocomplete',
  plugins: [querySuggestionsPlugin],
  openOnFocus: true,
});

It works with proposed index but it does not work with my index.
It seems I need to setup more things on my algolia project side.
Whats the minimun settup requiered to in order to only use the “category” attribute from my posts_index ?
Is there some way to access and analize the index used for this example ?
Is there some usefull doc/video to follow ?
Would you please help me?

Leandro.