If you are asking for top shape, here is the solution.
Make the two curves like picture
make a sweep surfave form curves
and use replace surface command like this
if you are asking about how you make angles etc like your second pic, make the corss shape in surface (just make top and bottom surfaces), make an assembly then put cross in assy. Make angles in single part or in individual ones and split the ends using cross surfaces.
May this help you.
As I assume you must some basics of Catia. So please make first sketch, then go for second. When you start making sketch, plz go to interset 3D elements at operations tool bar.
a point (cross shaped) appears at intersection of previous sketch and recent sketch plane. you must select it and press construction/standard element toggle switch.
now this point will convert to a thick point from cross. Now you make an arc that must touch this point. As this your both sketches must cross each other at one sketch plane.
now go to sweep command (in Genarative shape design workbench) and choose explicit in profile type (first one) then chose second sketch as profile and first sketch as guide and just click ok.