It’s actually quite easy!
ssid is the name of your network, so the same as you use when you try to login on your local wifi with your phone, and key is the password.
Once you generated the QR code and scanned it with your camera, you should be connected. Now all you do is click the menu button of the camera and check the IP left under, and fill that in in the app. And it should work! Let us know if you succeeded or need extra help