If you receive a 403 error message, it is because you are signed in with a personal Google account. You need to go to google.com and near the top right hand corner tap/click on your initial or picture and sign out. Then come back here and tap/click the Students button above and login with school email address and password.
If you login and keep getting redirected to this page every time you tap/click the Students button, it is because your schedule and class assignment has not been transferred to Canvas. Once your schedule and class assignment have transferred to Canvas then you will be redirected Canvas.