Will a 3 yr old dog and 3 month old puppy bond or is there too much age difference

a three year old dog should still be very active and have lots of energy, so the age should not make much of a difference. what matters more is if the 3 year old dog is generally ok around other dogs. try bringing the older dog to a dog park and see how he behaves around active dogs to get an idea of how he will react to a puppy. if you have two specific dogs in mind, a great way to introduce them is to take them on a hike on an off leash dog trail. this way they are in neutral territory and both are too busy exploring to be in each other's way but they can still get used to each other. as long as there isn't too many other people or dogs they should stay with you without too much problem. if an off leash, dog friendly trail isn't an option for you, try taking them on any walk with plenty of things for them to sniff and at first have one dog on either side of you. if they seem to be alright with each other, then you can let them be on the same side. if they start to get upset, try increasing your pace to a light jog to distract them a bit. once they calm down, you can slow to a walk again.
until you know that they are ok with each other, make sure they are supervised when they eat and don't just give them bones to chew on in case they fight over it.

What kind of dogs are they?