Login as another user without View setup and configuration permission

You need at least View Setup & Configuration, as there's no "Login" option from anywhere other than the setup screens. You don't need Modify All Data if you're a Delegated Administrator (which also requires View Setup & Configuration). There's little reason to restrict access to View Setup & Configuration, as there's not much you can do without additional permissions.

Steps to log in as another user in salesforce:

From Setup, enter Users in the Quick Find box, then select Users.

Click the Login link next to the username. This link is available only for users who have granted login access to an admin or in orgs where admin can log in as any user.

To return to your admin account, select User's Name | Logout.