How to Buy a WordPress domain

I have been looking all around google and everywhere I can think of and I can not figure out how to buy a wordpress domain or even launch my website as a example.www.remarpro.com. currently it is just localhost but I need to launch it so that or people can go on it and buy from my shop. I know that I can use wordpress.com but you cannot use plugins and I need the store plugin. Can someone please tell me how to launch my website?