I am creating first time real estate website so can you please tell me how to insert city list and areas in dropdown box
Is this using a theme? If so you should read the documentation or contact the author.
If it is for a theme you plan to sell then perhaps this is not the right category to be working in yet. If that is proving a challenge then you are likely to have quite a few bigger obstacles to overcome, and may be wiser to try in a simpler category.
I am using WP Residence theme
I’d expect it’s covered In the documentation but otherwise contact the author