Confirm sale and leave feedback

following text after a buy now
“”Congratulations, your item has been won!
The winner is: gast1 / gast 1
The winning bid is: €100
Next Steps;
1. Contact the winner (gast1@link2u.nl)
2. Arrange Payment and deliver item to the winner.
3. Confirm sale and leave feedback.
“”
step 1 and 2 I understand
but for step 3 I need a button I suppose voor confirming and a button for give feedback.

I don’t see buttons and I don’t understand it

I hope to read the answer