Hopefully this works.

Pages/Bits/Head.php

@@ -1,8 +1,20 @@
 <head>
     <meta charset="UTF-8">
-    <meta name="viewport" content="width=device-width, initial-scale=1.0">
+    <meta
+        name="viewport"
+        content="width=device-width, initial-scale=1.0"
+    >
 
-    <title>Sarah's garden</title>
+    <title>
+        <?= htmlspecialchars(
+            "SG/" . ($PageTitle ?? "Home"),
+            ENT_QUOTES,
+            "UTF-8"
+        ) ?>
+    </title>
 
-    <link rel="stylesheet" href="../../Styles/Style.css">
+    <link
+        rel="stylesheet"
+        href="<?= $RootPath ?>Styles/Style.css"
+    >
 </head>

Pages/Home.php

@@ -1,3 +1,9 @@
+<?php
+
+$PageTitle = "Home";
+
+?>
+
 <!DOCTYPE html>
 
 <html lang="en" data-palette="CatppuccinMocha">
@@ -38,7 +44,7 @@
 
             <p>
                 Speaking of introducing myself, you should probably visit the
-                <a href="HTML/Sarahtonin.php">page</a> about me.
+                <a href="./Sarahtonin.html">page</a> about me.
             </p>
 
             <h3>Credits</h3>

Pages/Sarahtonin.php

@@ -1,3 +1,9 @@
+<?php
+
+$PageTitle = "Sarahtonin";
+
+?>
+
 <!DOCTYPE html>
 
 <html lang="en" data-palette="CatppuccinMocha">