French Keyboard

I live in Quebec, Canada and have just bought a Microsoft french keyboard in error ( Optical Desktop with Fingerprint Reader) The Alt Car key to the right of the spacebar does not work when depressed with the numeric keypad just below the F1-F12 buttons. This, for example, I do not know how to get the question mark character. Here’s another situation. When I press just the greater than\less than button, I get a \ and shift 3, not the # not the forward slash it’s supposed. I;m all confused. I need your help, please.

Thanks

Minsang