Using a TextFields input

I am completing a swift challenge and below is the program so far. No doubt it is full of problems but I am slowly working them out. It is a maths game that presents the user with a random multiplication question. They insert their answer and it is either right or wrong. The thing that has me stumped at the moment is using the users input. I have a textfield with a $answer to accept their answer. I also have a func called checkAnswer but am not sure how to pass in the textfield value for answer. Can anyone assist please??

import SwiftUI

struct Test1: View {
    @State private var numberOfGames = 5
    @State private var gameNumber = 0
    @State private var showingGameOver = false
    @State private var firstChoice: [Int] = [0, 1, 2, 3]
    @State private var secondChoice: [Int] = [0, 1, 2, 3]
    @State private var score = 0
    @State private var answer = 0
    @State private var correctAnswer = 0

    var body: some View {
        NavigationView {
            VStack {
                Form {
                    Section("Choose 5, 10, or 15 games") {
                        Stepper("\(numberOfGames) Games", value: $numberOfGames, in: 5...15, step: 5)
                    }
                    Button {
                        createGame()
                    } label: {
                        Text("New Game")
                    }
                    .frame(maxWidth: .infinity, maxHeight: .infinity)
                    .background(Color.blue)
                    .foregroundColor(.white)
                    .cornerRadius(20)
                    Text("This is game \(gameNumber) of \(numberOfGames) games.")
                    Section {
                        HStack {
                            Text("\(firstChoice[0]) x \(secondChoice[0]) = ")
                            TextField("Enter your answer here", value: $answer)
//                            TextField("Enter your answer here", value: $answer, onCommit: {
//                                checkAnswer
                            }
                        }
                    }
                }
                .alert("The game is over.", isPresented: $showingGameOver) {
                    Button("Game over.", action: Reset)
                }
                
            }.navigationTitle("Maths Quiz")
        }
    
    func checkAnswer() {
        correctAnswer = firstChoice[0] * secondChoice[0]
        if correctAnswer == answer {
        }
    }
    
    func createGame() {
        var firstList = [Int]()
        var secondList = [Int]()
        
        for _ in 0...12 {
            firstList.append(Int.random(in: 0...12))
        }
        for _ in 0...12 {
            secondList.append(Int.random(in: 0...12))
        }
        firstChoice = firstList.shuffled()
        secondChoice = secondList.shuffled()
        gameNumber += 1
        if gameNumber == numberOfGames {
            showingGameOver = true
        }
    }
    
    func Reset() {
        score = 0
        gameNumber = 1
    }
}
    
    struct Test1_Previews: PreviewProvider {
        static var previews: some View {
            Test1()
        }
    }

Are you asking about how to pass the variable answer (which contains whatever the user enters into the text field) into the function checkAnswer? If so: The checkAnswer function already uses answer in its body. You don't need to pass answer into the function, and you shouldn't.

If this isn't what you're asking, then you need to clarify what you are asking. Please be as detailed as possible.

Furthermore, read the documentation for TextField.

Sorry for not replying earlier. Your reply made me have another look at my code and I worked things out. Thanks very much.