WebViewTest.swift

import SwiftUI
import WebKit //WebKitをインポート

struct WebViewTest: UIViewRepresentable {
 // var url: String = "https://google.com" //表示するWEBページのURLを指定
    func makeUIView(context: Context) -> WKWebView{
        return WKWebView()
    }
    func updateUIView(_ uiView: UIViewType, context: Context) {
    guard let path: String = Bundle.main.path(forResource: "index", ofType: "html") else { return }
        let localHTMLUrl = URL(fileURLWithPath: path, isDirectory: false)
        uiView.loadFileURL(localHTMLUrl, allowingReadAccessTo: localHTMLUrl)
    }
}
///////////////////////////
ContentView.swift

import SwiftUI
import WebKit

struct ContentView: View {
    var body: some View {
        NavigationView {
       NavigationLink(destination: WebViewTest()) {
        Text("Show web page")
        }
      }
    //    WebViewTest()
    }
}

struct ContentView_Previews: PreviewProvider {
    static var previews: some View {
        ContentView()
    }
}
//////////////////////////////
index.html