It's very important to have your pets secure when the vehicle is in motion. Small dogs can go in a securely tethered crate.
It's also so important when choosing a 'type' of dog, to do your homework. If it's a dog known to be a barker-you should reconsider if that will be a problem. Same with active breeds. Lot's of people choose a dog because it's small/cute. Those breeds can be a challenge to an inexperienced dog owner.
I recommend research, and training to build a bond with a dog rather than shocking, squirting, yelling, beating, confining, and eventually getting rid of the dog.
Owning a dog is a big responsibility, and not for everyone.