I need to have two users with different passwords but the same user settings and layout. The idea is for the Administrator to be able to login as user and to be able to work with user profile and make modifications to it.

In case of Windows 7 I was able to have the same user folder by linking the Users\Administrator folder to the user folder by a symbolic link. It works in Windows 10, but there are issues with default applications. Every time I login as a different user the default applications get reset (Mail client, Web browser, ...).

So I need to find a different approach, or to get the default applications function under control.

See if this works:
https://superuser.com/questions/1364764/clone-windows-user-settings

Otherwise you're going into the territory of LCP or GP, where you are to customize the Default profile and any new user account that gets created will use the Default as the base.

Sorry, but cloning will not do. I have to be able to modify the user profile acting as Administrator.

With cloning I would have to clone the user profile to Administrator login, then make modifications, then clone the profile back to the user. It's much simpler to change the user password, log in as user, then to make changes to the user settings, then to tell the user to change the password back.