You can see the motion too

Wow. Very interesting!

It's actually a really interesting question. It's commonly believed that on horses the vestigial remnants of additional toes/hooves/foot structure are the chestnuts and ergots. The first known horse had 3 and 4 hooves per leg!

This is a trimmed chestnut. They grow a material similar to a nail or horse hoof - ergots are similar, but in a different location. When they get big you just peel or clip it off. They can smell a bit strong when you trim them, but hooves smell worse when the farrier comes out!

Neigh. The picture is only showing from the (human) wrist down. Horse legs and most (all?) mammal quadruped legs actually pretty closely resemble each other.

what does it even mean to feel like a foot?