@Aditya_Kumar_Pandey - Hey! If you’re on Enterprise, you can do this with Script Actions. There’s even a free snippet shared in this post → Free snippets for "Custom Scripts" rule action in Asana
If you’re not on Enterprise, you can still have the subtask inherit the parent task values by using custom field variables when creating the subtask through rules. However, keep in mind this won’t update automatically if the parent task values changes.