Certified GKH Gardening Expert
I'm not sure if your tree is dead or just ailing. You should do a test to see if the branches have green underneath the bark, or if they are dry and break. Here's an article that will help you with that:
Also, it looks like there is a raised bed around the tree. If that is filled with soil, it can prevent the roots from getting the oxygen they need and will kill a tree over time.
Have you examined any of the remaining leaves and branches? This article will explain a lot about diseases that cherry trees get. You may be able to save this beautiful tree if it hasn't died: https://www.gardeningknowhow.com/edible/fruits/cherry/cherry-tree-diseases.htm I would encourage you to contact a certified arborist for advice.