how do i check all pending subscriptions on a certain payment method

I’m trying to get an app. The app is free and every time i try , not only that all i try any. Every time i try to download an app i put my apple id to confirm and then it closes the page to where it takes me to put my apple ID (which is normal) and then for a split second it’s normal then it redirects me to another page which is the settings page on my payment methods and then i try to remove my apple pay but it says that there is a subscription on it so i’m trying to find what that subscription is and cancel it