HOW TO DESIGN EARTHING AND LIGHTNING SYSTEMS IN BUILDINGS SUCH AS OFFICE BUILDING OR COMMERCIAL BUILDINGS ???? THANKS

With care, paying attention to the requirements, particularly those from the applicable codes. And, in general, having an experienced professional to do it or at least to supervise and review the whole design.

Agree with Leo. I designed both lighting and grounding systems early in my career, but learned how to do it from very experienced coworkers. On the one hand the design does not require a lot of math and is fairly straight forward. On the other, there can be numerous codes which must be followed for commercial, and thus public use buildings. The issue is safety of occupants. The old IEEE color book series gave guidance, but local codes must be followed.

Get familiar with the NEC section on general lighting loads. And grounding conductor sizing.