I cannot download any apps

See the Apple Support article(s) below. 

If you see a message that says 'Your account has been disabled in the App Store and iTunes' - Apple Support.   *

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Hi Abbas,

Welcome to the Apple Community, where some of us do our best to help each other.

Wondering if you noticed the "Related Article" link, above your question on this discussion page.

The article will likely help you.

Apple Support have other articles online that may help:

If you forgot your Apple ID password, or have issues when you try to sign in :

https://support.apple.com/en-au/HT201487

if you have forgotten the appleID itself :

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

If you’ve forgotten the answers to your Apple ID security questions

https://support.apple.com/en-au/HT201485

And:

If you make changes to your Apple ID:

What to do after you change your Apple ID or password:

https://support.apple.com/en-au/HT204071

For more:

Apple ID Support Page:

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

Hope something here helps you get ready to download apps again. :)