Dispay callback from paddle checkout for total price

I’m fumbling my way through adding Paddle checkout, but the thing that is stumping me is that I need to use callbacks ( apparently ) to show the price after tax is added. This is the example code from paddle, I literally just need to show the price, tax and total on the Webflow page itself, next to the inline checkout. Can anyone shine any light on this?

Any help at all would be really appreciated.


Here is my site Read-Only: LINK
(how to share your site Read-Only link)

tried this but nothing, is this completely wrong