How to allow a user to login on Domain Controller

                                                      Allow login locally

*In System one DC login as Administrator open the ADUC console and create user account *user1,user2, user3.
*open GPM console (open run and type gpmc.msc and click ok)
*expand forest
       ↳ Domainpreetam.com(domain_name)

                      ↳ domain controller

                                ↳ default Domain Controller right click and click edit

new windows will appear

*Expand computer configuration

                ↳ policy

                      ↳ windows settings

                             ↳ local policy

select user  and right  assignment 

• right click on allow log on locally click on a property
• click on add user or group 
• click on browse
• Type the username user1 click ok, ok, ok

After that update Group Policy

Verification

In System one Domain Controler server login user1 as a user.

access the resources.