Create a product page and add to cart that will save value , price , quantity of socks and display it nxt screen using firebase

How to create a Product page wherein the value of the item's price x quantity wil be save to firebase and it will be displayed on add to cart screen
Product order value x product >buy> reciept or value of product .

What i created so far is login but there is no guide and i followed Kodular it just i got stopped ny somwthing the kodular have (even i installed the extension.)