I want to give up my dog
Why would you give up your dog?
Yes, I don't have time for dogs
You are expected to fulfil the responsibly of having a pet if you own one. If you are unable to take care of your pets, you should find them a new home that will provide them the love they need.
Dog is 16 years old, can find home easily.
A dog that old will have a hard time, you should really work to make sure you can find him someone to go other than a shelter.