A comprehensive guide on how to take advantage of powerful QMK features through VIA is outside the scope of Aurora documentation.
We strongly recommend you to watch this tutorial by Austin V if you want to learn how to use VIA.
Aurora QMK PCBs can support multiple layouts. If you are using a layout other than the standard one, you need to enable support for it from the Layouts tab.
Make sure you have Test Matrix checked.
Refer to the following video by StrangetownFunk to learn how to test a PCB with metal tweezers. You can use VIA Key Tester mentioned above instead of the website in the video.