Intial general structure of source code and page.

src/pages/Main.tsx

@@ -0,0 +1,27 @@
+import "./styles/main.css";
+
+import { useParams } from "react-router-dom";
+import { Menu } from '../components/Menu';
+import { Header } from '../components/Header';
+import { SideNav } from '../components/SideNav';
+import { Program } from '../components/Program';
+import { NotFound } from '../components/NotFound';
+
+interface MainParams {
+    page: string
+}
+
+export const Main = () => {
+    const { page } = useParams<MainParams>()
+
+    return (
+        <>
+            <Header />
+            <section className="App-content">
+                <SideNav />
+                {page === "menu" ? <Menu /> : page === "program" ? <Program /> : <NotFound />}
+                <div style={{ width: 333 }} />
+            </section>
+        </>
+    )
+}