Will this carburettor fit a Honda Engine GCV190A D1EG NH1, No: GJAAA 8024377 ?

Unfortunately not, I am afraid this is the wrong one. It look like you need this - 16100 Z0Y 812 however this has been replaced by the below. 16100 Z0Y 813 - Carburettor - https://www.lsengineers.co.uk/catalog/product/view/id/163443#