User menu: Items selection
Items in Shop's Categories are represented by messages. Any interaction with the Items (Products) is carried out using the Inline buttons belonging to the corresponding message.
Add to Cart
An Item can be Added to Cart while continuing to select other Items.
Buy
The product can be Bought Directly - in this case, the purchased Item (product) will also be added to the Cart, and the user will be transferred to the Checkout section of the Cart.
Product with Variants (options)
If, when creating a product, it was assigned Variants, each having its own price, then the «Add to Cart» and «Buy» buttons will not be displayed until the user selects one of the Item's Variants. Once selected, the Item can also be Added to Cart or Bought Directly, just like products without additional options (Variants).