Yes please i cant let him continue to suffer as much as it hurts me i know hes hurting more and that i cant have! I dont know if you got the pictures i just sent
I did get the pictures. I think you're making the right choice putting him out of his misery, even though I know how hard it can be.
The methods I am going to suggest would be best performed by a man, or woman that is not afraid of killing living things. Having someone that is already emotional about ending the bird's life, and is afraid to do so is asking for problems to occur.
One method, and the one I use here the most, is to grab a log, and nail to nails in at V. Grab the duck, gently set its head in the bottom of the V, and do a quick chop with a very sharp ax. Other methods may include the "broomstick method", or cervical dislocation. I'll provide links regarding those two methods at the bottom of this post.
https://www.chickenfarmers.ca/wp-content/uploads/2014/05/CFC-Euthanasia-Guidelines.pdf
https://www.offthegridnews.com/how-to-2/the-4-most-humane-ways-to-kill-a-backyard-chicken/
https://ucanr.edu/sites/poultry/files/301025.pdf