I don't know why the item name shows "price" in the shopping cart.
My product variation type have 2 fields: Certificate choice (attribute) and Course period.
How can I customize my formatter in the cart?
The last image is my views "Cart form"
The price must be showing because that is all that is configured to be rendered for the referenced entity in whatever view mode it's defaulting to. If you want something like you've pictured, you're going to need to use the individual fields, which likely means adding another reference to get the attribute / value data, adding all three of the fields you want to render (course name, attribute value, and period), and then configuring the View to ensure all three of those fields are rendered into the single column.