There is so much evidence to support the perspective of a global flood from a Biblical, genetic, geological and biological perspective that I decided to send each link supporting the global perspective separately to you first.
I will try to compile my thoughts to tie the various links together into one cohesive answer. My concern is how to keep the article short without losing much of the impact and getting sidetracked in too much detail.
In any case, the short answer to the question is that there is overwhelmingly evidence that Noah’s flood was global.
Here are a couple of links supporting the global flood from an archaeological perspective.
And here is a link supporting the biological perspective: