Creating a project by clicking on the create button

Gantt
#1

When you click on the add button, a task-type lightbox opens, I need a project-type lightbox to open, and a task-type lightbox has already been called for project tasks

#2

Hello Danil,
You need to create a column with any value in the name parameter except the add value. Then you can return the HTML elements in the template function for the task rows and HTML element in the label parameter for the grid header:
https://docs.dhtmlx.com/gantt/desktop__specifying_columns.html#datamappingandtemplates

https://docs.dhtmlx.com/gantt/api__gantt_columns_config.html#:~:text=a%20column%20(PRO)-,label,-%3F%20-%20

Then you need to attach a custom function and use the createTask method to add a new task:
https://docs.dhtmlx.com/gantt/api__gantt_createtask.html

In the createTask method, you can specify the task type in the type parameter, then Gantt will show different lightbox types.

Here is an example:
https://snippet.dhtmlx.com/4nmc187d