How can I get the updated lag


Hello, I would like to ask how can I get the delay between tasks with dependency links when I move a task


If you want to set the link lag parameter after moving a task, there is no built-in way to do that. You need to implement a custom solution by using the Gantt API and Javascript.
You need to use the onAfterTaskDrag event handler and obtain all task links:
Then you need to update each link with the FS or SS type.
Here is an example of how it might be implemented: