The first slice of pie is always a mess. It's difficult to get out and usually looks awful when you do. There's an easy fix: Make the first slice a tiny "sacrificial" slice. That first sliver will give you enough of an opening to cut additional slices cleanly and get a knife or tool under so you can remove it easily.
This is a kitchen tip that's often saved me from serving broken slices of pie before with the bottom crust broken in half. Before I mastered this, I'd just take the beat-up piece for myself and give my guests or family the better-looking ones.
By taking a tiny slice out to begin with, you give yourself plenty of room to get that pie tool underneath the next slice when you cut it, and it makes removing the slices simple and easy. The photo above tells the tale, and you can figure out how it works, but The Kitchn has a few more details at the link below.