Newbie here, need some help for slidable horizontal button collection - ios

Question

I'm an utter and complete beginner to Xcode. I've joined this app developer internship, but they are implementing a self directed learning approach for our assignments and I am completely swamped. I have never done any kind of coding before, so I was hoping to get some answers here.
Here's the code:
import SwiftUI
struct ContentView: View {
#State private var didTap:Bool = false
var body: some View {
VStack {
HStack(spacing:320){
Button(action: {
didTap = !didTap
}
){
VStack {
Text("12").font(.largeTitle)
.foregroundColor(didTap ? Color.white : Color.black)
.fontWeight(.bold)
Text("Monday").font(.system(size: 11))
.foregroundColor(didTap ? Color.white : Color.black)
}.frame(width: 70, height: 80, alignment: .center)
.background(didTap ? Color.gray: Color.white)
.cornerRadius(20)
.shadow(color: .gray, radius: 5, x: 0, y: 6)
}
Text("")
}.background(.red)
Button {
self.didTap = true
} label: {
VStack {
Text("12").font(.largeTitle)
.foregroundColor(.black)
.fontWeight(.bold)
Text("Monday").font(.system(size: 11))
.foregroundColor(.black)
}.frame(width: 70, height: 85, alignment: .center)
.background(.white)
.background(didTap ? Color.blue : Color.yellow)
.cornerRadius(20)
.shadow(color: .gray, radius: 5, x: 0, y: 6)
}
ColorPicker(/*#START_MENU_TOKEN#*/"Title"/*#END_MENU_TOKEN#*/, selection: /*#START_MENU_TOKEN#*/.constant(.red)/*#END_MENU_TOKEN#*/)
.padding(.trailing,180)
}
}
}
struct ContentView_Previews: PreviewProvider {
static var previews: some View {
ContentView()
}
}
This is my app's home page design
Home page
And this is what I've got so far
After hours of trying and reading
My app is a simple reminder app. There are a lot to work on but I'm trying to make a collection view comprised of buttons that show the dates in a user's current week. If you click the buttons, the date along with the reminders will change to reflect the selected date. You are also supposed to be able to swipe left or right to change into the previous / next weeks.
Appreciate any kind of feedback since I am such a moron when it comes to these kinds of tech-y stuff.