On Day #1, I learned the basics of the Swift UI such as VStack, HStack and ZStack. Also, used struct to group the code and make it simple.

import SwiftUI

struct ContentView: View {
    var body: some View {
        ZStack{
            LinearGradient(gradient: Gradient(colors: [.blue,.white]), startPoint: .topLeading, endPoint: .bottomLeading)
                .ignoresSafeArea(.all)
            VStack{
                Text("Cupertino, CA")
                    .font(.system(size: 32, weight: .medium, design: .rounded))
                    .foregroundColor(.white)
                    .padding()
                VStack(spacing: 10){
                    Image(systemName: "cloud.sun.fill")
                        .renderingMode(.original)
                        .resizable()
                        .aspectRatio(contentMode: .fit)
                        .frame(width: 180, height: 180)
                    
                    Text("76°")
                        .font(.system(size: 70, weight: .medium, design: .rounded))
                        .foregroundColor(.white)
                    HStack{
                        WeatherDayView(DayOfWeek: "TUE", Weather: "cloud.sun.fill", temperature: 74)
                        
                        WeatherDayView(DayOfWeek: "WED", Weather: "cloud.fog.fill", temperature: 71)
                        WeatherDayView(DayOfWeek: "THR", Weather: "cloud.heavyrain.fill", temperature: 66)
                        WeatherDayView(DayOfWeek: "FRI", Weather: "cloud.drizzle.fill", temperature: 64)
                        WeatherDayView(DayOfWeek: "SAT", Weather: "cloud.fog.fill", temperature: 68)
                        
                    }
                   
                }
                Spacer()
            }
        }
    }
}

struct ContentView_Previews: PreviewProvider {
    static var previews: some View {
        ContentView()
    }
}

struct WeatherDayView: View {
    var DayOfWeek: String
    var Weather: String
    var temperature: Int
    var body: some View {
       
        
        VStack{
            Text(DayOfWeek)
                .font(.system(size: 20, weight: .medium, design:.rounded))
                .foregroundColor(.white)
            Image(systemName: Weather)
                .renderingMode(.original)
                .resizable()
                .aspectRatio(contentMode: .fit)
                .frame(width: 40, height: 40)
            Text("\\(temperature)°")
                .font(.system(size: 20, weight: .medium, design:.rounded))
                .foregroundColor(.white)
            
        }
    }
}