This is a broad topic. You might want to start by finding a domain name via one of the Domain Name Services. If your requested domain name is available you can register it. Next you will need to find a web hosting service. Here is just one link to find the top ten web hosting, or do your own search:
top ten web hosting
Some providers you can register both domain name, and will provide web hosting. I have always had good service with
www.namezero.com. There are many others service providers as well.
Some of the hosting providers will offer a windows based service. Others, may provide a Mysql, or linux, php platforms, or both. Most host providers will have a real simple to use web page generator, point and click to build your first web pages.
Some have mentioned Go Daddy, but looking at the top ten web hosting searches, they are not on the top of the list. I was surprised that the my providers was near the top of the lists.
Here is another place to search for your domain:
http://www.namezero.com
Good luck.