Look in the Layers panel. Some of the layers might be locked. You can also try Object > Unlock All on Spread. Finally, ckeck to see if the template is set up on the master page. Command-Shift (Mac) or Control-Shift (Windows) clcik on objects to override them. This means the object is copied from the master page to the spread you are working on, Now you can move, delete, or modify it.