Can my itunes id/pw be different from apple id/pw?

Get him his own iTunes account.

He can get a $10 iTunes gift card to open it. No CC needed.

-> iTunes Store: How to redeem an iTunes Gift Card

I do not have an iTunes Store account

1. Install the latest version of iTunes. You can download iTunes (it's free) from the Download iTunes webpage. If iTunes is already installed on your computer, check your version and update if necessary.
2. Open iTunes.
3. In the Source pane (on the left side of the iTunes window), click iTunes Store.
4. In the upper-right corner of the iTunes Store window, verify that the button says "Sign In." If this button displays an email address instead, click the button and then click Sign Out.
5. In the QUICK LINKS window in the right-hand column, click Redeem.
6. In the resulting screen, enter the 16-digit code printed on the back of the card (it starts with an "X"), then click Redeem.
7. In the resulting screen, create your new iTunes Store account. You will have the option to enter credit card information; if you do not wish to do so, click the None button on the Payment screen.
8. Once you've successfully redeemed your gift card, the credit amount will appear next to your account name in the upper-right corner. Each time you purchase items, iTunes will deduct funds from the credit until it's depleted. If a pending purchase exceeds the credit amount, iTunes will ask you to enter a credit card number. You do not need to re-enter your gift card number to make multiple purchases.