What is iTunes mean

Hi zelalern162

Welcome top the Apple Community.

Apple require a payment method to be entered in your Apple ID account,

before the first time you use the App Store or iTunes,

even if you are only downloading "free apps" etc.

Payment methods that you can use with your Apple ID:

https://support.apple.com/en-au/HT202631

How to Change, Add or Remove Apple ID Payment methods

https://support.apple.com/en-us/HT201266

After you have used the App Store and  iTunes for the first time, 

it is possible to remove the payment method.

Hope this helps you :)