Yes, you could add a new line to your account using self-serve. You can follow the procedure here https://www.koodomobile.com/add-a-line

Regarding the “specific phone number”, Koodo would give you a new number based on what they had in the number pool. You could also change the number later using selfserve once you activate new Koodo number.

Thanks. Is there any way to know if it's possible to get a specific number? 

Or can I cancel if I can't get the number? She's picky!

There was a limited number in the pool. Not sure if that can satisfy her. You can always contact a Koodo rep and ask them to look for something special but nothing is guaranteed.

Yes, you can cancel the line. it should be noted in the contract agreement.

Thank you.