Locked out of phone

Most likely locked due to entering the wrong passcode too many times. Follow this support article to reset your passcode using your Apple ID and password. After your device is locked due to wrong passcode entered too many times, the iPhone will have to be erased, so hopefully you have a recent backup.

If you see an iPhone or iPad unavailable message or Security Lockout screen - Apple Support

If your Apple ID password was entered incorrectly too many times, then there is this support article to reset your Apple ID password.

If your Apple ID is locked or disabled - Apple Support

See this support article: If you forgot your iPhone passcode - Apple Support