OK. First question is what type of machine are you using Orbiter on? If you are using a laptop, it is highly advisable to purchase and install an external keypad. Secondly, have you read the Orbiter manual?
Cheers and welcome to our universe.
StarLost
BTW, I have both 2010 and 2016 installed on my desktop and have no problems with the numerical side of the keyboard. My laptop is a different matter and needed the external keypad for both versions. Solved my problem so I didn't have to remap the keyboard.