Design of antenna with hfss

hi everyone, i would design an antenna with hfss but the structure is too complexe and i'am new on hfss, so any help please

I am afraid you have to make the structure there is no else possibility.
If you are new then Youtube has some amazing tutorials which can help you at least will provide you with some starting point.
For complex structures sometimes line form helps where you draw a part of structure and then using HFSS commands generate the complete structure but I am afraid there is no else way