The login form widget is a good widget. Another thing you can look at is the authentication widgets.
Hope this helps!
Edit: I also want to add that I've had issues with the login form widget not working with internet explorer in the past (this could be fixed now). The authentication widgets worked fine.
I think you should take a look at the "Login form" widget.
create a page with login widget and give access to anonymous user and call this page using a microflow.
add this microflow as default home page in navigation.