iphone 6 disabled and cannot connect to itunes

Hve a look at these articles -

If your computer doesn't recognize your iPhone, iPad, or iPod

If your computer doesn't recognize your iPhone or iPad - Apple Support

iOS device not showing in iTunes for Windows

iOS device not showing in iTunes for Wind… - Apple Community

If you forgot the passcode on your iPhone, or your iPhone is disabled or unavailable -

Click on the link for instructions on how to reset your passcode without a computer if you have iOS 15.2 or higher.

How to remove your iPhone, iPad, or iPod touch passcode without a computer - Apple Support

Click on the link for instructions on how to reset your passcode using a computer.

If you forgot your iPhone passcode - Apple Support