How to dismiss any View Controller without using Storyboard ? and do I have to use UINavigationController to achieve this ? if not how then ?
The way to dismiss a view controller is to call a dismiss method on the presenting view controller. If you presented your child controller from a parent by calling self.present(_:animated:) then you can call self.dismiss(animated:). If you used a navigationController and called navigationController.push(_:animated:) then you need to tell the navigation controller to dismiss with navigationController.popViewController(animated:)
Method names might not be exact, but you should be able to figure it our with autocomplete.