Store user selected language in session storage.

src/pages/languageSelection.jsx

@@ -28,8 +28,12 @@ function languageSelection() {
             gap: '1rem',
             marginTop: '1rem'
         }}>
-        <BlackButton text="ภาษาไทย" to='/introduction'/>
-        <BlackButton text="English" to='/introduction'/>
+        <BlackButton text="ภาษาไทย" to='/name' onClick={(e) => {
+            setLang("Thai");
+        }}/>
+        <BlackButton text="English" to='/name' onClick={(e) => {
+            setLang("English");
+        }}/>
         </div>
         </div>
     );