The Canon Print Inkjet/Selphy app is designed to work on Android devices and iOS devices. The app will not work on the Chrome OS. If you are trying to connect the printer to your Chromebook, you can connect the printer using a generic printer connection.
You can connect the printer to your Chromebook using the steps below.
If you do not have the printer's IP address, you can print the network settings using the steps found in the link HERE.