I need help with this part i have no idea what to do
You might want to look up a video about Chang3D on YouTube, it might provide some insight! Otherwise, try learning Ming Cat's pattern and behavior, use the obstacles that separate you from it, and hear its 'meows', it will tell you when its tired! Also, don't step on the puddles on the floor! ...
Overall, don't try to outrun it. Outsmart it.