I have a few questions on chihuahuas?

You can get plenty of information by just Googling the breed. Just a couple of points I'd like to bring up. First, if you have a senior dog, bringing a puppy or a young dog into the home is not the best idea. Your older dog will have little patience for a young dog that wants to play all the time, and one well placed 'warning' could seriously injure such a small breed. most of the rest is about training and socialization. A chihuahua, no matter how small is still a dog. The way you social and train is going to have the most impact on the dog you end up with, so if you start out with the idea of having a doll you can dress up & carry around, you'll create a little monster. Go the the Chihuahua Club of America website, where you can learn about the breed, health issues and get breeder referrals in your area. Most of what you read about the breed will be stereotypes and have it's roots in bad ownership