Out of box, probably not (though I never looked into it). However, you can write plugins (for example in C++), so if you can find a PowerPoint parser (not sure if the format is open) you could convert it into something Godot can understand.
Or a simpler idea, export the presentation as JPGs, which I'm pretty sure you can do in PowerPoint, and then load and display them as a TextureRect in Godot. That should be pretty easy.