How can I change this program to make it show the users pulse?

Hey, y’all. I found a program and wanted to modify it to show the pulse of a user. I am relatively new to the HealthKit framework. Can you guys help me? I tried to modify them myself, but that just went horribly wrong(let’s not get into the details :wink:) My code is below:
ContentView.swift:

import SwiftUI
import HealthKit

struct ContentView: View {
    
    private var healthStore: HealthStore?
    @State private var steps: [Step] = [Step]()
    
    init() {
        healthStore = HealthStore() 
    }
    
    private func updateUIFromStatistics(_ statisticsCollection: HKStatisticsCollection) {
        
        let startDate = Calendar.current.date(byAdding: .day, value: -7, to: Date())!
        let endDate = Date()
        
        statisticsCollection.enumerateStatistics(from: startDate, to: endDate) { (statistics, stop) in
            
            let count = statistics.sumQuantity()?.doubleValue(for: .count())
            
            let step = Step(count: Int(count ?? 0), date: statistics.startDate)
            steps.append(step)
        }
        
    }
    
    var body: some View {
        
        NavigationView {
        
     List(steps, id: \.id) { step in
Text("\(step.count)")
Text("\(step.date)")
}
            
        .navigationTitle("Just Walking")
        }
       
        
            .onAppear {
                if let healthStore = healthStore {
                    healthStore.requestAuthorization { success in
                        if success {
                            healthStore.calculateSteps { statisticsCollection in
                                if let statisticsCollection = statisticsCollection {
                                    // update the UI
                                    updateUIFromStatistics(statisticsCollection)
                                }
                            }
                        }
                    }
                }
            }
        
        
    }
}

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

And my Health class:

import Foundation
import HealthKit

extension Date {
    static func mondayAt12AM() -> Date {
        return Calendar(identifier: .iso8601).date(from: Calendar(identifier: .iso8601).dateComponents([.yearForWeekOfYear, .weekOfYear], from: Date()))!
    }
}

class HealthStore {
    
    var healthStore: HKHealthStore?
    var query: HKStatisticsCollectionQuery?
    
    init() {
        if HKHealthStore.isHealthDataAvailable() {
            healthStore = HKHealthStore()
        }
    }
    
    func calculateSteps(completion: @escaping (HKStatisticsCollection?) -> Void) {
        
        let stepType = HKQuantityType.quantityType(forIdentifier: HKQuantityTypeIdentifier.stepCount)!
        
        let startDate = Calendar.current.date(byAdding: .day, value: -7, to: Date())
        
        let anchorDate = Date.mondayAt12AM()
        
        let daily = DateComponents(day: 1)
        
        let predicate = HKQuery.predicateForSamples(withStart: startDate, end: Date(), options: .strictStartDate)
        
        query = HKStatisticsCollectionQuery(quantityType: stepType, quantitySamplePredicate: predicate, options: .cumulativeSum, anchorDate: anchorDate, intervalComponents: daily)
        
        query!.initialResultsHandler = { query, statisticsCollection, error in
            completion(statisticsCollection)
        }
        
        if let healthStore = healthStore, let query = self.query {
            healthStore.execute(query)
        }
        
    }
    
    func requestAuthorization(completion: @escaping (Bool) -> Void) {
        
        let stepType = HKQuantityType.quantityType(forIdentifier: HKQuantityTypeIdentifier.stepCount)!
        
        guard let healthStore = self.healthStore else { return completion(false) }
        
        healthStore.requestAuthorization(toShare: [], read: [stepType]) { (success, error) in
            completion(success)
        }
        
    }
    
}

and finally, my model:

import Foundation

struct Step: Identifiable {
    let id = UUID()
    let count: Int
    let date: Date
}

Please help me! Thank you so much, this is the best forum ever! :heart_eyes: