How to create a horizontal menu with icons and content and subcategories

I am currently creating a horizontal menu bar with both images and text with buttons in the header bottom section, but when I click it, it only leads to another page. I want to make a menu with both icons and text like my current design and have an additional feature when pointing to it, it will open many subcategories like on the demo (without using the horizontal menu button on the demo). What should I do? I hope you can guide me.

Best Regards