download.swift

//https://developer.apple.com/documentation/foundation/urlsession/1411511-downloadtask

let url = URL(string: "https://www.shanecowherd.com")!

let downloadTask = URLSession.shared.downloadTask(with: url) { (downloadedFile, response, error) in
    
    // Make sure the temporary file exists and you have access to it
    guard let downloadedFile = downloadedFile, FileManager.default.fileExists(atPath: downloadedFile.path) else {
        return
    }
       
    //downloadedFile - The location of a temporary file where the server’s response is stored. You must move this file or open it for reading before your completion handler returns. Otherwise, the file is deleted, and the data is lost.
    
    let fileData = try? Data(contentsOf: downloadedFile)
                                                              
    let fileString = String(data: fileData, encoding: .utf8)
}
downloadTask.resume()