Check out example codes for "shapes in swiftui". It will help you in understanding the concepts better.

Code Example 1

struct ContentView: View {
    var body: some View {
        ZStack {
            Rectangle()
                .fill(Color.black)
                .frame(width: 200, height: 200)

            RoundedRectangle(cornerRadius: 25, style: .continuous)
                .fill(Color.red)
                .frame(width: 200, height: 200)

            Capsule()
                .fill(Color.green)
                .frame(width: 100, height: 50)

            Ellipse()
                .fill(Color.blue)
                .frame(width: 100, height: 50)

            Circle()
                .fill(Color.white)
                .frame(width: 100, height: 50)
        }
    }
}

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