You part appear to have zero draft with the exception of the curved surface. According to the analysis, the draft line is at 15 degrees of the round feature. You could do this with a sweep where the sweep would could be a surface with the edge at the desired location.
The way you have this post defined, you would have an undercut if you placed the parting line as you show in the second image. Maybe we are not understanding your goal?
My goal is very simple.
I want to know other way to make draft lines without mold option.
I want to know way to make it with standerd features.
I will give up if we can't make it without mold option.
What Antonius said. If you split it there, it is undercut, because the front wall is straight.
There must be a different part you are working on that is slightly different?
Like if that straight wall is drafted in, then the radius has to be split, is that what you want?
The easiest way to make that line is to draft the wall before adding the round feature.
To do it after the fact, you would use a sweep feature with the 15 degrees locked in the sketch.