How to set salary structure?

Hi There,
In my company salary processing is 20 of every month, i.e. each employee is paid there salary on 20 of every month.
My question is How i can do it?
and other thing is can you please explain me from date and to date in salary structure.
I mean what it describes.
And also how can i set an employee payroll processing to 20 of every month.
Suppose if there is an employee who have joined the company on 9th septemebr so on 20th of the month he must be paid the amount for the number of days he have worked.
Can you please let me know!

Sir i have been through this already.
But my questions arent being answered by this so thought of making a topic.
Please look into it.
And also Base salary must be Monthly or yearly in the following image let me know!

@saurabh6790 any update?

Hi there any update on this?

I think you need to have custom script for that.