try this tutorial Ellpitical Orbit its a old c2 tutorial but for sure will work on your end.
basically is using Cos() and sin()
and this is the 2nd circular/eliptical motion one but might be a bit complicated. cause it has to many variables.
but to rotate a object around a point u basically calculate it like this
position x centerX + cos( A*B ) * circumferenceX
position y centerY + sin( A*B ) * circumferenceY
centerX and centerY are like for example the position of a planet you want a moon to spin around it.
curcumferenceX and circumferenceY will make the circular motion change around a 3d plane of sorts(it moves in a 2d plane but altering live the values of A*B and circumferenceX or Y it will make it look like is a 3d sphere - very similar to the 2nd tutorial i linked). if u make circumeferenceY less than circumferenceX ul see it go on a smaller Y motion while keeping same X width motion.
cos(A*B) and sin(A*B) calculates moons position relative to the position of the planet in degrees * circumferenceX or Y (not sure if i explained it the right way but that's how i understand it).