Downloaded Tree Problem

Hey, so I created this grassland in Blender and then I downloaded a
free tree that someone had made in a separate blender project. When I render the tree, the leaves don’t look like leaves, they look like giant balloons. Does anybody know how to fix this or help me see the tree with it’s leaves in a different view? Please let me know, I’m a noob to Blender so if you could give me as much details as possible that would be great!

Thanks!

Without seeing anything, like the tree, its pretty hard to give you an answer…