Hi How to set deadline to a task that is going to be created?I need to set the d

Please go through below link to answer your question
forum.appian.com/.../Defining_Task_Completion_Deadlines.html

@rajasekharh Would you please be able to let us know the place where the priority calculation will be done? If it is going to be in the same task(which you want to set deadline) and if you want to set the deadline of the same task based on the value in the priority, you may do as follows:
1. Create a utility process model that sets the task deadline upon accepting the task id and the priority(There is a smart service available under cloud approved shared component namely Task Management and this helps you to set the deadline based on task id)
2. Trigger the process created above by using fn!startprocesswrite(available as cloud approved plugin by name Start Process Writer)and the saveInto of the Priority field is the right place for doing so.

If you are already aware of the priority value prior to creating a task, then calculate the deadline as well, and then this should be straight forward and 'Others' tab in the User Input Task holds the deadline setting.

@rajasekharh657 - I would recommend same approach as suggested by sikhi. Other approach can be to save the priority in database and create a rule to calculate deadline before the task in process model or set the deadline rule directly others tab.

Thanks all.Appreciate all the info