Hello Anantharam,
The flag NoAutoPro (or "Flag to Create Project Automatically") in the Item Type customizing controls whether the system will automatically set flag "Create Project on Saving" when creating an item. Specifically, if flag NoAutoPro is set, the flag to automatically create the project will not be set in the frontend.
If you do not wish for this flag to be set per default when creating an item, you should ensure that "NoAutoPro" is set in the item type customizing. There is no other way to control this.
Best regards
Francesco