Couldn't sign in my itune and app store

What happens when you try? Error message(s)? More information would help. ID Disabled?

If you see a message that says 'Your account has been disabled in the App Store and iTunes' - Apple Support. https://support.apple.com/en-us/HT208856

If necessary, contact iTunes Support. Either use the form or scroll to the bottom of the page in the 2nd link. Follow through the screens to get a chat or telephone option.

iTunes Store - Contact Us - Official Apple Support. https://support.apple.com/en-euro/itunes-contact

iTunes Support – world wide https://support.apple.com/choose-country-region/itunes

If not a disabled ID, do you have access to another WiFi network where you can try? That has worked for several people.

Try a restart.

Restart your iPhone, iPad, or iPod touch https://support.apple.com/en-us/HT201559

Try a forced restart.

Reset Device. https://support.apple.com/en-us/HT201412

If necessary

Hard reset. https://www.wikihow.com/Hard-Reset-an-iPhone

Do a backup and try a factory reset. Then restore from your backup.

Restore to Factory setting. https://support.apple.com/en-us/HT201252

Backup - Restore your device from an iCloud or iTunes backup. https://support.apple.com/en-us/HT204184