A Coinbase account isn't a wallet.
You don't have any private keys - they do.
That number you see listed as your balance is the amount of Coinbase's bitcoins they promise to spend on your behalf.
If you want to actually own Bitcoins, you need to use a Bitcoin wallet.
It's unfortunate that rampant false advertising in this space has resulted in new users not understanding that difference between a Bitcoin wallet and a Bitcoin bank account.
Thanks for the info. I did not know that Coinbase was not a wallet as I opened it to transfer BTC to my bank account and then realized that it is only dealing with US accounts. Then I opened a Blockchain wallet and added the coinbase BTC address to it but required a private key to add those bitcoins. I guess I will need to get those bitcoins withdrawn to another BTC address.