How to get a random item list in Firestore with Flutter and show it in a GridView

how can i get random item something mix everytime user open the app. right now i having a gridview that show item but not randomly. i just get all of the data in firestore and show it into gridview with unlimited length of item that look like this

 @override
  Widget build(BuildContext context) {
    final productProvider = Provider.of<ProductProvider>(context);
    List<Product> productsList = productProvider.products();
    return Column(
      children: [
        Column(
          children: [
            Padding(
              padding: const EdgeInsets.symmetric(horizontal: 8.0),
              child: Row(
                mainAxisAlignment: MainAxisAlignment.spaceBetween,
                children: [
                  const Text(
                    'Suggestion Products',
                    style: TextStyle(fontSize: 20, fontWeight: FontWeight.w600),
                  ),
                  TextButton(
                      onPressed: () {
                        Navigator.of(context).pushNamed(
                          FeedsScreen.routeName,
                          arguments: 'popular',
                        );
                      },
                      child: const Text('view all')),
                ],
              ),
            ),
            Padding(
              padding: const EdgeInsets.symmetric(horizontal: 10.0),
              child: SizedBox(
                width: double.infinity,
                child: Column(
                  children: [
                    GridView.builder(
                      shrinkWrap: true,
                      physics: const NeverScrollableScrollPhysics(),
                      itemCount: productsList.length,
                      gridDelegate:
                          const SliverGridDelegateWithFixedCrossAxisCount(
                              crossAxisCount: 2,
                              childAspectRatio: 2 / 3,
                              mainAxisSpacing: 1,
                              crossAxisSpacing: 15),
                      itemBuilder: (ctx, i) {
                        return ChangeNotifierProvider.value(
                          value: productsList[i],
                          child: const MainProduct(),
                        );
                      },
                    ),
                  ],
                ),
              ),
            ),
          ],
        ),
      ],
    );
  }

and how can i achieve an suggestion product base on what user history search. kinda look like some o ecommerce app do. when i search for a computer in the app. in the suggestion will suggest me some related product. thanks