Go to Setup -> Conversions and create a new conversion specifying the name and the price.
This will generate a conversion tag ( $conversion-tag )
Locate your thank you page and add the following script
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Save and publish it to the web.
For adding dynamic conversions with name and price, add the following properties:
orderName: either order number ( Order 51522 ) or product name
orderPrice: either order price or product price
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Just make sure not to add a conversion tag ( starting with $ ) under tags, as it will create a duplicate conversion