I have already tried spline lines and polyline. I just want to join the points so that they form a curve, its not a perfect ellipse therefore I am not able to get the desired result from the ellipse tool. I have attached the image, I want connect the purple points into a curve help is very much appreciated, thank you.
You can use a spline and that will give you something round, but won't exactly represent the geometry. I would recommend doing this project in a 3D CAD software like Autocad Inventor, Autodesk Fusion360, or SolidWorks. In those software programs you can extrude to a plane, then project to a different plane; over and over again, giving you lots of options for geometric manipulation without the math. The sketch tool will be called "project" or "convert entities" depending on the software you use.
