https://thinkdiff.net/ios/how-to-create-radio-button-and-group-in-swiftui/

RadioButtonGroups.swift

//MARK:- Group of Radio Buttons
enum Gender: String {
    case male = "Male"
    case female = "Female"
}

struct RadioButtonGroups: View {
    let callback: (String) -> ()
    
    @State var selectedId: String = ""
    
    var body: some View {
        VStack {
            radioMaleMajority
            radioFemaleMajority
        }
    }
    
    var radioMaleMajority: some View {
        RadioButtonField(
            id: Gender.male.rawValue,
            label: Gender.male.rawValue,
            isMarked: selectedId == Gender.male.rawValue ? true : false,
            callback: radioGroupCallback
        )
    }
    
    var radioFemaleMajority: some View {
        RadioButtonField(
            id: Gender.female.rawValue,
            label: Gender.female.rawValue,
            isMarked: selectedId == Gender.female.rawValue ? true : false,
            callback: radioGroupCallback
        )
    }
    
    func radioGroupCallback(id: String) {
        selectedId = id
        callback(id)
    }
}