How to set up pass-through authorization in Gitlab?

Question

LDAP

Good afternoon, please tell me, is there the latest version of Gitlab, RedHat7 and Active Directory on the Intranet network.
I got to AD authorization: https://docs.gitlab.com/ee/administration/auth/how... I
started reading, as I understand it, you need to configure this file from the manual for our AD to enable login from AD login, BUT! I didn’t find it anywhere, but is there a pass-through authorization (SSO or whatever it is called), but the bottom line is that when a user enters the gitlab website, he automatically logs in, and if the user wants to log in as root, he would press Exit, and only then did the authorization form appear.