AdMob integration on iOS

I’m trying to implement banner ads from Google.MobileAds/Firebase. I’m following this guide: https://components.xamarin.com/gettingstarted/firebaseiosadmob I was able to configure my app and enable firebase analytics but when I try to implement public void AddBanner() into the monogame project I get errors:

Error CS0246: The type or namespace name ‘CGPoint’ could not be found (are you missing a using directive or an assembly reference?) (CS0246) (word_game.iOS)

Error CS0029: Cannot implicitly convert type ‘word_game.Program’ to ‘UIKit.UIViewController’ (CS0029) (word_game.iOS)

Error CS0103: The name ‘View’ does not exist in the current context (CS0103) (word_game.iOS)

Here’s my code:

using Google.MobileAds;

namespace word_game
{

public class Game1 : Game
{
	
	const string bannerId = "ca-app-pub-3940256099942544/6300978111";

	BannerView adView;
	bool viewOnScreen = false;

	public void AddBanner()
	{
		// Setup your BannerView, review AdSizeCons class for more Ad sizes. 
		adView = new BannerView(size: AdSizeCons.Banner, origin: new CGPoint(0, 0))
		{
			AdUnitID = bannerId,
			RootViewController = this
		};

		// Wire AdReceived event to know when the Ad is ready to be displayed
		adView.AdReceived += (object sender, EventArgs e) => {
			if (!viewOnScreen)
			{
				View.AddSubview(adView);
				viewOnScreen = true;
			}
		};

		var request = Request.GetDefaultRequest();
		// Requests test ads on devices you specify. Your test device ID is printed to the console when
		// an ad request is made. GADBannerView automatically returns test ads when running on a
		// simulator. After you get your device ID, add it here
		request.TestDevices = new[] { Request.SimulatorId.ToString() };

		// Request an ad
		adView.LoadRequest(request);
	}

	public Game1()
	{
		graphics = new GraphicsDeviceManager(this);
        graphics.IsFullScreen = false;

	}

	protected override void Initialize()
	{
		base.Initialize();
        screenWidth = GraphicsDevice.Viewport.Width;
        screenHeight = GraphicsDevice.Viewport.Height;

        tileSize = ((screenWidth - 200) / width);
        Console.WriteLine(screenWidth + " " + screenHeight);

	}

	protected override void LoadContent()
	{
		// Create a new SpriteBatch, which can be used to draw textures.
     }

    protected override void Update(GameTime gameTime)
    {
        base.Update(gameTime);

	

    }

    protected override void Draw(GameTime gameTime)
    {
        base.Draw(gameTime);

        graphics.GraphicsDevice.Clear(Color.Green);

		
	}
}
}