How to implement the movement of celestial bodies in the Unity Engine?

Question

Physics

Hello. I need to implement the movement of celestial bodies in orbits. How to draw the future orbit, knowing, for example, the initial velocity of the body? As a result, I need some kind of maneuver planner in the game Kerbal Space Program. Maybe tell me some formulas, links, ways to implement this. Physics grade 10 is clearly not enough here.