|I think you may be confusing a local domain name with a public domain name.|
If your business name is naah than you would use naah.local for your domain name. This is for internal use only.
Now if you wanted to have domain name email like email@example.com or do your own web hosting you would need a public registered domain name.
If all the naah's of com, net, org etc are used currently you would need a different name for your public domain.
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