added 404 page component

src/client/src/components/nosuchpage.js

@@ -1,9 +1,19 @@
 import * as React from "react";
 import { BrowserRouter as Router, Link, Route, Routes } from "react-router-dom";
-import Home from '../FrontPage';
+import { Typography } from '@mui/material'
 
 export default function NoSuchPage() {
-    
-}
-
-
+    return(
+    <>
+        <Typography type="h3">
+            This page does not exist
+        </Typography>
+        <Typography type="h4">
+            The page you are looking for does not exist or has been moved
+        </Typography>
+        <Link to="/">
+            Return to the home page
+        </Link>
+    </>
+    )
+}