Drill down hierarchical data with UITableView

Hello,

I'm attempting to create a drill-down UITableView with xml data and believe I need to use linked-lists, etc but have no clue where to start/what I'm doing. I'm currently doing something like this for each page but just realized that it was totally the wrong way to go about doing it.

import UIKit
class MasterTableViewController: UITableViewController, XMLParserDelegate {
   
    var mainCat: [MainCategories] = []
    var eName: String = String()
    var mainCategoriesTitle = String()
   
    override func viewDidLoad() {
        super.viewDidLoad()
       
        if let path = Bundle.main.url(forResource: "01 - MainCategories", withExtension: "xml") {
            if let parser = XMLParser(contentsOf: path) {
                parser.delegate = self
                parser.parse()
            }
        }
    }
   
    override func didReceiveMemoryWarning() {
        super.didReceiveMemoryWarning()
        /
    }
   
    /
   
    override func numberOfSections(in tableView: UITableView) -> Int {
        return 1
    }
   
    override func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
        return mainCat.count
    }
   
    override func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
        let cell = tableView.dequeueReusableCell(withIdentifier: "Cell", for: indexPath)
       
        let mCaty = mainCat[(indexPath as NSIndexPath).row]
       
        cell.textLabel?.text = mCaty.mainCategoriesTitle
       
        return cell
    }
   
    override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
        if segue.identifier == "LevelTwo" {
            if let indexPath = self.tableView.indexPathForSelectedRow {
               
                let controller = segue.destination as! LevelTwoTableViewController
               
                let mCaty = mainCat[(indexPath as NSIndexPath).row]
                controller.selectedName = mCaty.mainCategoriesTitle
/
            }
        }
    }
   
    func parser(_ parser: XMLParser, didStartElement elementName: String, namespaceURI: String?, qualifiedName qName: String?, attributes attributeDict: [String : String]) {
        eName = elementName
        if elementName == "mainCat" {
            mainCategoriesTitle = String()
        }
    }
   
   
    func parser(_ parser: XMLParser, didEndElement elementName: String, namespaceURI: String?, qualifiedName qName: String?) {
        if elementName == "mainCat" {
           
            let mCat = MainCategories()
            mCat.mainCategoriesTitle = mainCategoriesTitle
           
            mainCat.append(mCat)
        }
    }
   
   
    func parser(_ parser: XMLParser, foundCharacters string: String) {
        let data = string.trimmingCharacters(in: CharacterSet.whitespacesAndNewlines)
       
        if (!data.isEmpty) {
            if eName == "title" {
                mainCategoriesTitle += data
            }
        }
    }
}