Fixing dead links (#10917)

Author: niels9001

README.md

@@ -10,7 +10,7 @@
 </p>
 
 <h3 align="center">
-  <a href="https://aka.ms/windev">About WinUI</a>
+  <a href="https://learn.microsoft.com/windows/apps/winui/winui3/">About WinUI</a>
   <span> · </span>
   <a href="https://learn.microsoft.com/windows/apps/desktop/">Documentation</a>
   <span> · </span>
@@ -36,7 +36,7 @@ For WinUI, your app's users must be on Windows 10 1809 - Build 17763 or newer (i
 
 The full documentation of WinUI can be found on [Microsoft Learn](https://learn.microsoft.com/windows/apps/desktop/):
 - [Get started with WinUI](https://learn.microsoft.com/windows/apps/get-started/start-here)
-- [Build your first WinUI app](https://learn.microsoft.com/windows/apps/how-tos/hello-world-winui3)
+- [Build your first WinUI app](https://learn.microsoft.com/windows/apps/tutorials/winui-notes/)
 - [WinUI & Windows App SDK samples](https://github.com/microsoft/WindowsAppSDK-Samples)
 
 </br>