SwiftUI - Loading image with DispatchQueue

Question

I understand how to utilize DispatchQueue with UIKit, but not with SwiftUI, because HorizonCalendar requires SwiftUI to function. Everything works perfectly, however as I browse down and load an image, the scrolling lags. I attempted to add DispatchQueue, however the SwiftUI rejected it. How can I include DispatchQueue in this code so that it may load images while scrolling?

Main ViewController

import UIKit
import SwiftUI
import HorizonCalendar

class TheGalleryView: UIViewController {
    override func viewWillAppear(_ animated: Bool) {
        let textAttributes = [NSAttributedString.Key.foregroundColor: colorTint]
        navigationController?.navigationBar.prefersLargeTitles = true
        navigationController?.navigationBar.largeTitleTextAttributes = textAttributes
        navigationItem.leftBarButtonItem?.tintColor = colorTint
    }
    
    override func viewDidLoad() {
        super.viewDidLoad()
        title = getString(rawString: "Gallery")
        navigationItem.leftBarButtonItem = UIBarButtonItem(image: UIImage(systemName: "gear"), style: .plain, target: self, action: #selector(openSetting))
        
        view.backgroundColor = UIColor(named: "Main Background")
        
        createCalendar()
    }
    
    func createCalendar() {
        let calendar = Calendar.current
        
        let startDate = calendar.date(from: DateComponents(year: 2023))!
        let endDate = calendar.date(from: DateComponents(year: 2023, month: 12, day: 31))!
        
        let content = CalendarViewContent(calendar: calendar,
                                          visibleDateRange: startDate...endDate,
                                          monthsLayout: .vertical(options: VerticalMonthsLayoutOptions()))
            .interMonthSpacing(25)
            .dayItemProvider { day in
                ZStack {
                    if getFirstPhotoFromGallery(fromDay: day.components) != nil {
                        Image(uiImage: getFirstPhotoFromGallery(fromDay: day.components)!)
                            .resizable()
                            .aspectRatio(contentMode: .fit)
                            .cornerRadius(7)
                            .opacity(0.4)
                    }
                    Text("\(day.day)")
                        .font(.system(size: 17, weight: .semibold))
                        .foregroundColor(Color(UIColor(named: "Font Color")!))
                }
                .calendarItemModel
            }
        
            .interMonthSpacing(24)
            .verticalDayMargin(8)
            .horizontalDayMargin(8)
        
        let calendarView = CalendarView(initialContent: content)
        calendarView.daySelectionHandler = { day in
            // MARK: The date has been selected
        }
        
        calendarView.translatesAutoresizingMaskIntoConstraints = false
        calendarView.backgroundColor = UIColor(named: "Main Background")
        view.addSubview(calendarView)
        calendarView.topAnchor.constraint(equalTo: view.safeAreaLayoutGuide.topAnchor).isActive = true
        calendarView.leadingAnchor.constraint(equalTo: view.safeAreaLayoutGuide.leadingAnchor).isActive = true
        calendarView.bottomAnchor.constraint(equalTo: view.safeAreaLayoutGuide.bottomAnchor).isActive = true
        calendarView.trailingAnchor.constraint(equalTo: view.safeAreaLayoutGuide.trailingAnchor).isActive = true
    }
}

Extension code, to load the image from data core

func getFirstPhotoFromGallery(fromDay: DateComponents) -> UIImage? {
    var prePhoto = UIImage(systemName: "")?.withTintColor(.clear)
    
    let freshDate = Calendar.current.date(from: fromDay)
    
    let getDailyData = theDailyData.first(where: { $0.date == freshDate })
    
    if getDailyData != nil {
        let searchTheImage = thePhotoData.first(where: { $0.belongTo == getDailyData?.theID })
        if searchTheImage != nil {
            let getPhoto = UIImage(data: (searchTheImage?.thePhotoData)!)?.jpegData(compressionQuality: 0.25)
            prePhoto = UIImage(data: getPhoto!)
            // This doesn't accepted the return inside the DispatchQueue
        }
    }
    
    return prePhoto
}