I usually take the train with my dog but if you're flying since your dog isn't a service dog and they're too big to fly in the cabin they'd have to fly in the cargo hold so you'll need to get an airline approved crate for it.

Usually to get a dog to fly in cargo you would need to get approval through the airline and a clean bill of health from the vet. The vet may be able to get you some info about the process too