I have to create drag and drop custom control.
We provide 2 ways to create your own custom controls:
via Control Designer: This enables the users to create, and design their UI controls with a variety of options available at their fingertips. This includes creating elements, providing states, giving styles, writing CSS, and more. These are mainly display purpose controls. You can further look for more related articles on our community page.
via Control Editor: This helps users build their own UI components from scratch and make them available to the broader community within their organization to drag & drop. You can further refer to this article to know more about Creating a control using Control Editor
Control Editor will need you to be well-versed with Coffee scripts, JS, handlebars & CSS.
I hope this helps.