How to make an industrial safety helmet in catia

do you have a picture or sketch of your design?

do you have dimensions for the head size?

do you have design specs? material, strength, etc.?

here some stuff that might help you:

https://grabcad.com/questions/how-to-model-helmet-fullface-helmet-as-in-motorcycle-helmet-using-catia-v5r21

You should be familiar with tools from part, assembly and mainly surface and wireframe workbench. Surface workbench will help much for free form shapes of helmet.

This is a tutorial for SOLIDWORKS, but it should give you a method to follow: https://www.youtube.com/watch?v=Kg3u5CJ59LU