This post i have mentioned the steps how to join Windows 10 PC to the Azure Active directory
First, you would need to create Azure trail subscription by following the below link.
Once you are signed in the cloud service you will be issued with a default domain name that has the following format : .onmicrosoft.com. In the Management portal, Click Active Directory in the left pane and you can find the default domain name or you can add your own custom domain name to the cloud service.
Create a new user in the Active Directory:
Now we are going to join Windows 10 to Azure AD using new user account. Goto -> Start Menu -> Settings -> System -> About on the Windows 10 machine. Click Join Azure AD