Ellipse

I just started learning CAD and I am currently working on a part that needs a reverse fillet. I already looked for answers on the forum and reddit, but all the ones I found worked by just removing a certain shape (e.g. a circle) from the edge, wich only works with straight parts. In my case I need that reverse fillet…

I am trying to generate an ellipse with a fixed minor axis length and a vertical major axis, the length of which can be solved so that the ellipse fulfills the following constraints: it is coincident with the first point of a spline, tangent to the spline in that point, and tangent to a circle in its outer (convex) side,…