Read the steps in the Reset your password section of Admin Sign In in our user guide.
Below are the critical usage notes.
Before using the Forgot your password form, enable outgoing emails using your Project Web Interface.
If you cannot find the message with a Reset Password link, check your Junk Email folder. The name of the email is Password Reset Confirmation for Admin Username.
If you cannot restore or reset the password for the existing user, you can create a new Admin user and set a password for this user. To do so, take the following steps:
bin/magento admin:user:create --admin-user=%user_name% --admin-password=%your_password% --admin-email=%your_email% --admin-firstname=%admin_user_first_name% --admin-lastname=%admin_user_last_name%