How to dismiss a Tab Bar Controller from inside one of its own tabs?

I am building a new app. My auth flow presents a tab bar controller with 5 tabs at the end.

In my login screen, it presents the tab bar controller after successful login:

let vc = MainTabBarVC()
vc.modalPresentationStyle = .fullScreen
self?.present(vc, animated: true)

On the tab bar controller, inside the last tab (My Settings VC), there is a log-out button. How can I dismiss the tab bar entirely with this log-out button's action and return to the login screen? I am trying to dismiss the entire tab bar controller from inside one of its tab.

Solved:

Thanks to @Paul and @HangarRash for comments. As @Paul told me in the comments, I changed the root view controller, and it worked perfectly. My code:

        let vc = LoginVC(authManager: authManager)
        
        if let delegate = UIApplication.shared.connectedScenes.first?.delegate as? SceneDelegate {
            guard let window = delegate.window else { return }
            UIView.transition(with: window, duration: 0.3, options: .transitionCrossDissolve, animations: {
                window.rootViewController = vc
                window.makeKeyAndVisible()
            }, completion: { completed in
                // Something maybe later
            })
        }