How do I update by payment method?

Here is guidance from Apple for updating your payment method→If you need to change or update your Apple ID payment method - Apple Support

Update your payment method on your Mac

1. Open the App Store.
2. Click your name or the Sign In button.
3. Click Account Settings.
4. Next to Payment Information, click Manage Payments. (If you're using an older version of macOS, click Edit next to Payment Type.)
5. Click Add Payment, then enter the new payment method. Click Done.