If all you want is to animate an object in a circular path, you can create a curve3d: https://docs.godotengine.org/en/stable/classes/class_curve3d.html

with a pathfollow child:

https://docs.godotengine.org/en/stable/classes/class_pathfollow3d.html

then, you just add your object as a child of the pathfollow. To move the pathfollow along the path, just modify its progress_ratio. This technique also works for other, more complicated, paths.