How do I programmatically hide or show the button in a scene's view controller that seques to next scene – Ios swift

create an outlet to your button in the view controller class:

@IBOutlet weak var startButton: UIButton!

and then in whichever function you want you can show hide it, I assume you want it hidden by default So in view did load you can do

override func viewDidLoad()
{
    startButton.isHidden = true
}

and then show it somewhere else

func doSomethingAndShowButton()
{ 
     // Do some other stuff
     ...

     // Show the button
     startButton.isHidden = false 
}