Why is downloading apps trying to charge me

When it comes to App Store apps, there are four fundamental types, each with its unique characteristics and payment models:

1. Free Apps (Get): Free apps are those that users can download and use without any initial cost. These apps do not require any upfront payment to access their basic features and functionalities. Developers often offer free apps as a way to attract a broader audience and increase user adoption. The revenue for such apps typically comes from other sources, such as in-app advertisements or in-app purchases.
2. Freemium Apps (Get with In-App Purchase): Freemium apps, also known as "free-to-play" or "freemium" models, are free to download and use at a basic level. However, to unlock additional features, content, or functionality, users are prompted to make in-app purchases. These purchases may be one-time payments or recurring subscriptions that grant access to premium content or services within the app.
3. Paid Apps (Price will be displayed in place of GET): Paid apps require users to make a one-time payment upfront before they can download and access the app. Once purchased, users usually have complete access to all features and content without any further payments. The advantage of paid apps is that they are generally free from advertisements and additional in-app purchases.
4. Paid Apps with In-App Purchase: This category combines elements of both paid and freemium models. Users are required to pay an initial one-time fee to download the app, granting access to its core functionalities. However, similar to freemium apps, developers may offer additional content or services through in-app purchases or subscriptions, allowing users to further enhance their app experience.

See the Pic below (For Sl 1, 2, 3 & 4 Marked linked to above answer)

If one or more of the following 6 options are true then you can't choose None as a payment method then the Billing information is needed. The "None" option will not appear...

1. If you have an unpaid balance or payment due
2. If you have a subscription that automatically renews
3. If you're using the iTunes Store or App Store for the first time
4. If you are not in the country or region you’re creating an Apple ID for
5. If you changed your country or region
6. If you're a part of Family Sharing

If you can't download, make purchases or update apps, including free apps, you need to update your payment method or add a new one. If you already verified that a payment method is available in your country or region and you're still having trouble, learn more.