Just add a button widget and then double click on it to open the properties. On the options you will see General and under that you will see Icon. Select the icon you want and that will then be on the button. Then the Caption must be empty to show only the icon.
A save button can be added very easily. Simply add a “Save button” widget by right clicking on your page. Clicking the button will commit your object to the database. Nothing more or less. Printing is more difficult. What do you want to print, or better: how? You probably don’t want to print exactly what is shown on your screenshot, so you first have to make sure you have something in a layout in the way you want to print it.
Then there are several widgets in the Mendix marketplace that might help. Just click the shopping cart icon in Studio Pro and then search for print and check your options.