The CRV Garmin does not appear to indicate actual accuracy but when I use my motorcycle Zumo in the same location, I get 3 metre accuracy showing on that second screen.
As for adding an additional language that is not already on your automotive device, use the garmin express app and a computer. You will need this app and a computer to download updates for maps as well. These instructions should point the way. You cannot physically attach the crv garmin to a computor with a cable but need to go through the steps in the nav manual preparing and using a usb memory stick.
Garmin Support Center for Canada is where you will find answers to frequently asked questions and resources to help with all of your Garmin products.
support.garmin.com