Hello, I've never bought a domain name before, so where should I be going to properly and safely buy one? Thanks.
There are hundreds of domain registrars, so chances are that if you've heard of the company then it should be fine. In the past I've used UK-Cheapest, Namecheap, Ionos, GoDaddy, and CloudFlare. Usually comes down to who has the best price, and how lazy I want to be convenient I want it to be to integrate with other products & services I might be using.
One other question, from what I've seen, many domain hosts aren't exactly transparent with their costs. They suggest the domain can have a domain name based email address also, is this usually at additional costs do you know?
Usually, you'll get at least one free email address related to the domain. It won't have much storage though; probably 2GB or less.
