How do I remove payment method

You can only remove a payment method if you re-add a payment method.

Correction: You only cannot remove it if you have something (a subscription or you are a Family Sharing Organizer) that requires one be present. Otherwise you do not need to add a new one to be able to remove the old one.

You will need to have a payment method on file in order to use the app store

Correction: You do not need to have a payment method in order to use the App Store. I use the App Store to update apps and occasionally download some. I don't even have any balance in my account. As long as you are only downloading free items then you shouldn't need a payment method (or at least I do not).

To find out how to remove a payment method, and what to do if you can't remove your last payment method or use no payment method with your Apple ID, read this article --> Remove a payment method from your Apple ID - Apple Support

Unexpired subscriptions and Family Sharing organizers must always have a payment method present. To edit the cards used for those you may need to first add the new card and make it the primary payment method before removing the old card (see: If you need to change or update your Apple ID payment method - Apple Support ).

You can only remove a payment method if you re-add a payment method. You will need to have a payment method on file in order to use the app store