If you have approved ownership claim over your nonprofit profile, you can access the nonprofit dashboard pages by logging in here. After signing in, it will lead you directly to the Nonprofit Stats page if you have only one claimed nonprofit. If you have claimed more than one nonprofit, it will show you a list of organizations you have ownership of (click the one you want to manage).
You can always go back to the dashboard pages by clicking the welcome greeting on the top navbar and select “Manage My Nonprofit.”