I am using NOrmcore for Multiplayer, and I was wondering if there is any documentation on making a login-password system?

You will want to just use PlayFab, it is much better than building your own and they handle password recovery. You get a whole web user interface to manage the players. It is literally a few lines of code to authenticate. Similar to below, you will need your own user interface to allow them to enter a username/password and register and another user interface for login.

https://playfab.com/

         if (AppSettings.IsRegistered)
         {
             print($"Using email and password to autlogin: {AppSettings.EmailAddress}");
             var requestEmail = new LoginWithEmailAddressRequest { Email = AppSettings.EmailAddress, Password = AppSettings.Password };
             PlayFabClientAPI.LoginWithEmailAddress(requestEmail, OnAutoLoginSuccess, OnAutoLoginFailure);
             return;
         }
         else
         { 
 #if UNITY_STANDALONE
             var requestCustomId = new LoginWithCustomIDRequest { CustomId = SystemInfo.deviceUniqueIdentifier, CreateAccount = true };
             PlayFabClientAPI.LoginWithCustomID(requestCustomId, OnAutoLoginSuccess, OnAutoLoginFailure);
             return;
 #endif
 #if UNITY_ANDROID
             var requestAndroid = new LoginWithAndroidDeviceIDRequest { AndroidDeviceId = SystemInfo.deviceUniqueIdentifier, CreateAccount = true };
             PlayFabClientAPI.LoginWithAndroidDeviceID(requestAndroid, OnAutoLoginSuccess, OnAutoLoginFailure);
             return;
 #endif
 #if UNITY_IOS
             var requestIOS = new LoginWithIOSDeviceIDRequest { DeviceId = SystemInfo.deviceUniqueIdentifier, CreateAccount = true };
             PlayFabClientAPI.LoginWithIOSDeviceID(requestIOS, OnAutoLoginSuccess, OnAutoLoginFailure);
             return;
 #endif
         }