ContentView.swift

import SwiftUI
import SpriteKit
struct ContentView: View {
let screenWidth  = UIScreen.main.bounds.width
let screenHeight = UIScreen.main.bounds.height
var scene: SKScene {
let scene = GameScene()
scene.size = CGSize(width: screenWidth, height: screenHeight)
scene.scaleMode = .fill
return scene
}

var body: some View {
SpriteView(scene: scene)
.frame(width: screenWidth, height: screenHeight)
.ignoresSafeArea()
}
}
///////////////////////////
GameScene.swift

import SpriteKit
import GameplayKit
class GameScene: SKScene {
override func didMove(to view: SKView) {
backgroundColor = .yellow
physicsBody = SKPhysicsBody(edgeLoopFrom: frame)
}
func touchDown(atPoint pos : CGPoint) {      
 }
func touchMoved(toPoint pos : CGPoint) {       
}    
func touchUp(atPoint pos : CGPoint) {   
}
override func touchesBegan(_ touches: Set, with event: UIEvent?) {
guard let touch = touches.first else { return }
let location = touch.location(in: self)
let box = SKSpriteNode(color: SKColor.red, size: CGSize(width: 50, height: 50))
box.position = location
box.physicsBody = SKPhysicsBody(rectangleOf: CGSize(width: 50, height: 50))
addChild(box)
}
override func touchesMoved(_ touches: Set, with event: UIEvent?) {      
}
override func touchesEnded(_ touches: Set, with event: UIEvent?) {
}    
override func touchesCancelled(_ touches: Set, with event: UIEvent?) {
}  
override func update(_ currentTime: TimeInterval) {
 }
}