Select face of a cylinder an extrude surface

Hello, usually on a rectangular surface, there are

4 faces, but when you use radius on rectangle it creates a cilinder surface when extruded, is there a way to create 4 faces even when it’s a cilinder object, or recreate this face with the curvature?..I am trying to project some hexagonal faces and such. (1.0 MB)

If you want a solid you can extrude a planar surface, instead of a curve, and if your openings are planar you can cap them.