Last year Google rebranded their business apps to G Suite. This quick video may help you decide if this Google product is worth exploring further!
When you have an SSL certificate, users can connect to your site via the HTTPS protocol. The "S" in HTTPS stands for "secure". Although we use the term "SSL", which is the one most people are familiar with, the standard has actually been superseded by something called TLS (Transport Layer Security). But you don't need to worry about this because TLS is going to be enabled by default on any modern web server.
Make sure your email client is set up to display your name and email address correctly. Use a meaningful name for yourself, e.g. "Patrick O'Conner" or "ABC Windows". Do not use non-specific names or names which won't mean anything to some people, e.g. "Buddy" or "The Girls".
Most people tend to want to go for a .com, but getting the domain name you really want maybe more difficult as many .com's have already been registered. Going for a country specific domain registration will mean you have a better chance of getting what you want and it immediately tells others where you are based.