improved ground structure

frontend/src/App.tsx

@@ -1,8 +1,17 @@
 import "./App.css";
-import Button from "@mui/joy/Button";
+import { BrowserRouter, Route, Routes } from "react-router-dom";
+import { MainForm } from "./pages/MainForm";
+import { SuccessPage } from "./pages/SuccessPage";
 
 function App() {
-  return <Button variant="solid">Hello world</Button>;
+  return (
+    <BrowserRouter>
+      <Routes>
+        <Route path="/" element={<MainForm />} />
+        <Route path="/success" element={<SuccessPage />} />
+      </Routes>
+    </BrowserRouter>
+  );
 }
 
 export default App;