My uncle was dead last 2 years ago.. But it's really urgent to unlock his I phone 6s+ plz help me

 take the device, the original purchase receipt with the serial number, and a photo ID to the nearest Apple Store. Also take a copy of the death certificate and a copy of the will or a document that shows you inherited it.

How to request access to a deceased family member's Apple accounts

Genius Bar Reservation US

or contact Apple ID Support. They will need to see the original purchase receipt/paperwork also.

Apple ID Support

Apple ID Support (2) 

Apple Support by e-mail or chat         

Apple Support using Twitter

Or fill out and submit this form.

No one here can help you with that.

You likely need a court order to get Apple to help you, but there is no guarantee. Apple is very big on privacy.

ASC - Late 2012 Mac mini, macOS 10.15.2; Watch, series 5 GPS/cellular, watchOS 6.1.1; iPad Air 2, ipadOS 13.3; iPhone 8+, iOS 13.3; TV 4th Gen, tvOS 12.4.1;  HomePods, audioOS 13.3 and Airport Express w/ Airplay 2