How to create product groups in the online store if it's created on the Shopify platform? I need additional options.

If you want to have additional advanced options for products, then I advise you to use special applications that are developed by professionals for e-commerce on the Shopify platform. This is what works well for these stores, this is the software that many online store owners use and it's unlikely to have bugs. I would advise you to read more about this application https://apps.shopify.com/grouped-products . It seems to me that this is what you are looking for. There are also additional features that you can also use for your marketing strategy and increase sales in your online store.