When you create a new web part page you will notice that it does not have the quick launch on the left like sites do. If you would like to add it to your page you need to delete the code that is hiding it. Follow these simple steps:
1. Open the Page in Designer by clicking “Edit in Designer”.
2. Click “Advanced Mode”.
3. Find this code around line 34 and delete it.
4. A few lines down find these three lines and delete them.
5. Save the page.