Hi Patrick,
You can follow steps below to add custom URLs as tiles with steps below:
- Add the Promoted Links app by clicking Site Contents > add an app > Promoted Link.
- Open the app, and click LIST on the ribbon > Current View, and select the All Promoted Links view.
- Click new item to add your custom URLs, and input the required information, like Title, Link location and Launch Behavior.
- Go to edit the home page, click INSERT on the ribbon > App Part and select the app created above.
- Save the change, and the tiles will appear on the home page.
Regards,
Jiaxing Bian