Retrieve specific element from dynamic array in SwiftUI

Right, I'm new to swift(ui) and have been experimenting - my current issue is to do with a basic card app. I have generated a deck of card objects (in this case 10 items) and first displayed them all in a stack using a ForEach loop - no problem there. I then went on to pull out one card from the array to display on it's own nd this is where everything comes to a crashing halt. I suspect it's something simple and obvious but how do I get a single card from my deck for display?

struct Card: Identifiable, Equatable{
let id = UUID()
var factor1: Int = 0
var factor2: Int = 0
var product: Int = 0
var possibleAnswers: [Int] = []
}
struct CardView: View{
let card: Card
var body: some View{
    VStack {
    VStack { // Actual Card
        Spacer()
            Text("\(card.factor1) X \(card.factor2)")
                .font(.title)
                .foregroundColor(.black)
               // .bold()
                .multilineTextAlignment(.center)
                .padding(.horizontal)
                Spacer()
    }
    .padding()
    .frame(width: 300, height: 200)
    .background(
      Rectangle()
           .foregroundColor(cardColor(of: card))
    )
    
        HStack {
            Spacer()
            ForEach(card.possibleAnswers, id:\.self) { answer in
                Text("\(answer)")
                    .foregroundColor(.black)
                    .frame(width: 75, height: 50)
                    .background(
                      Rectangle()
                           .foregroundColor(cardColor(of: card))
                    )
                Spacer()
            }
        }
        .padding()

    }
}

func cardColor(of card: Card) -> Color {
    return Color(red:228/255, green: 229/255, blue: 229/255)
}
}

class Deck: ObservableObject {
@Published var numberCards = 10
@Published var cards = [Card]()

func buildDeck() {
    cards.removeAll()
    let cardCount = 1...self.numberCards
    for _ in cardCount {
                // Set up new card
                var myCard = Card()
                myCard.factor1 = .random(in: 1...12)
                myCard.factor2 = .random(in: 1...12)
                myCard.product = myCard.factor1 * myCard.factor2
                myCard.possibleAnswers.append(myCard.product)
                for _ in 0...2{
                    myCard.possibleAnswers.append(Int.random(in: 1..<145))
                }
                myCard.possibleAnswers.shuffle()
                // add card to the deck
                self.cards.append(myCard)
    }
}

var count: Int {
    return cards.count
}
}


struct ContentView: View {
@StateObject var deck = Deck()
var body: some View {
    VStack {
        Button(action: {
                deck.buildDeck()
        }) { // button text
            Text("Click to add card. Current Number of cards in deck: \(deck.count)")
        }
        Spacer()
    ZStack {
//             ForEach(deck.cards) { card in
        if let card = deck.cards[0] {
           CardView(card: card)
        }
//           }
    }
        Spacer()
    }
}
}