Domain

I currently have a domain I purchased and was wondering how do I go about changing it? Is it not possible? A charge on changing it? or do I have to purchase a new one?
If I do make a new domain on any of the above methods and I delete my shopify can I still access my domain/make changes to it in the code? Im just curious as currently Im using etsy and I have shopify but not really using shopify.

Hi,

Please connect here https://help.shopify.com/