Yes, you can start a presentation directly from the dashboard, you can select all elements on this page in the Content Structure at the same time and you have many different shortcuts available in our editors.
To start a presentation from the dashboard, hold down the Shift key and click on the presentation:
To select all elements on this page in the Content Structure at the same time, press "Ctrl + A"/"Cmd+ A". To add the elements to the current selection (e.g. all elements on the next page), press "Shift+Ctrl+A"/"Shift+Cmd+A".
The shortcuts of our editors you will always find at the bottom left of the presentation editor, in the Slide Editor, in the Template Editor as well as in the dropdown when starting a presentation and in the Enter menu.