Hello tell me how to change the template in libreoffice draw?
You need to open the master slide: View > Master.
After selecting the Master, you will see that at the bottom the tab is called “Backgrund”. So you can modified all you need.
Even Styles and Formatting (F11 oder Sidebar). Save all at the end as template. You can set this template as your default one or select whenever you need.
I also recommend to have a look at the guidelines for Draw: http://www.libreoffice.org/get-help/documentation/