How can i change email of administator?

Can you please elaborate your requirement so that I can assist you accordingly?

If you want to change the email address of your account. This can be done on the Profile page. 

If you want to change the recipient email address of the Email Notification, please check this guide as well:

How to Find and Change the Email Address Used for Notification Email?

How-to-Properly-Add-Change-and-Test-a-New-Email-Recipient-Address