How do I stop my apple TV payment but keep my icloud payment through paypal

Do you mean apart from canceling a subscription entirely to one of those? There is no simple way to use multiple payment methods.

The payment system is automated:

How App Store and iTunes Store purchases are billed - https://support.apple.com/HT201359

"Which payment method is charged?

When you buy items or pay for subscriptions, Apple attempts to charge your payment methods in this order:

1. Apple attempts to use your Apple ID balance to cover the full amount.

2. If you don't have Apple ID balance or you don't have enough to cover the full amount, Apple attempts to charge your primary payment method. The primary payment method is at the top of the list in Settings on your iPhone. You can control which payment method is at the top of the list.

3. If there's a problem with the primary payment method, or if the primary payment method can't be charged for the full remaining amount, Apple attempts to charge your other payment methods in order from top to bottom. If none of them can be charged, Apple may try again.

Unfortunately you can't tell it to pay one thing with one card and another with a different one. The closest you can get is to move another payment mthod up to the primary payment method when you want that card to be used. If you want to use PayPay for one thing and not for another then you need to either use Apple ID balance in the correct amount, or you need to keep moving payment methods. Either that or use a different Apple ID for the various cards and their subscriptions/payments, but that has its own nightmare of complications and is best avoided.