Yes, as @pbacot notes there are really two very different questions here.
Realistically you can’t make a staircase with a varying ‘pitch’, everyone would fall over trying to walk either up or down it.
So the questions really are
how would you place ‘steps’ equally along this curve?
how would you make a staircase work in a sloped location?
Various plugin and methods work with the first, but the second requires an understanding of the local regs and the use of a straight line that flattens the curve.
Just for a model is one thing, for real life planning it is another.