1. On the left menu, click Setup then Domains.
2. Snap Add domain.
3. Enter the name of the area you need to include, at that point click Next.
4. Pick how you need to check that you possess the space.
a. On the off chance that your space is enrolled at GoDaddy or 1&1, pick Sign in and Office 365 will set up your records consequently.
b. You can have an email sent to the enrolled contact for the space with a check code. On the off chance that you don’t perceive or approach the email on record, you can utilize choice 3.
c. You can utilize a TXT record to check your space. Select this and snap Next to see guidelines for how to add this DNS record to your enlistment center’s site. This can take up to 30 minutes to check once you’ve included the record.
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5. Pick how you need to roll out the DNS improvements required for Office to utilize your space.
1. Pick Add the DNS records for me in the event that you need Office to arrange your DNS naturally.
2. Pick I’ll include the DNS records myself in the event that you need to connect just particular Office 365 administrations to your space or on the off chance that you need to skirt this for the present and do this later.
6. Snap Finish – you’re finished!
For more details, visit : Add a domain to Office 365