No, we can set you up with an email provider (generally, Google for Business) and help you get everything working so you can take the keys.
You have to register it for at least 2 years, but we recommend registering for several years at once so you don't have to worry about it. Many of our clients decide to do 5 or 10 years at a time.
It can be! You want to make sure you trust the company who is managing your domain and ensure that you are still the owner of it (the company should act like a custodian) should you decide to move it later.