Hi,

The question and the context are not very clear, but I'll give it a shot: If you want a domain name (e.g. a .COM), you'll need a suitable provider first. I'll just take a wild guess here and assume that you're actually user of the Magix online services/Website Maker, even if you didn't specify that. In this case, you'd need to make sure that you're actually using one of the paid accounts. The free accounts obviously don't give you the possibility to register and host a domain for your site. Here's a comparison chart of the different Website Maker account types and their features:

http://www.magix-online.com/uk/offerings__prices.1611.html

If you do have an "Easy" or "Deluxe" account, you can register your domain name through the appropriate option in the Control Center of Website Maker. Note how one domain name is already included in the basic hosting fee with the "Deluxe" account. Here you would just have to use the bonus domain registration option in the Control Center.

I hope this helps. If you need more info, please make sure to ask a more specific question and include more details about the context. Thanks.