Whole document with single pages

1. Go to “File” and then choose “Document setup”
2. Uncheck “Facing pages”

Just one page displayed alone

1. Open the “Pages”-window (f12)
2. Select the page you want to be displayed alone
3. Press the little menu option in the top right corner
4. Uncheck “Allow selected spread to shuffle”
5. Drag and drop this page into a new position

Good luck!