Yes you can.
1. Open an Internet browser (e.g. Microsoft Edge, Mozilla Firefox, Google Chrome, Apple Safari, ...).
2. Enter app.sdui.de in the address line.
Click here on "Choose school" to find your school in Sdui. This will take you to the following page.
Enter either the name of your school or, alternatively, the school's postcode into the input field and select your school accordingly from the proposed schools.
You will then be taken to your school's login page, which looks like this:
Instead of "Sdui GmbH" in the header, the name of your school should appear. If this is not the case, click on "change" to find your school again.
This is your school's login page. Enter your login data here to log in.