You can either take the very simple programm from the first tutorial (Create and build a new project) or use some other AVR project you have created.
The upload is not done by the plugin itself. Instead it uses a tool named "avrdude". This tool is included in the winAVR toolchain on Windows. On Linux and MacOS this tool usually comes in a separate package. Take a look at the project wiki on how to get avrdude for your platform.
Once avrdude is installed, the plugin will usually find it automatically. To check that the plugin has found avrdude open the AVR preferences (Window > Preferences... > AVR) and check that no error symbol (
) is shown next to the AVRDude entry. If avrdude is not found automatically you need to manually change the path to point to the avrdude executable.
Programmers are the interface between your development system and the target MCU. There are many different programmers on the market today - starting from very simple build-yourself parallel port hacks up to elaborate USB JTAG devices. If you do not yet have a programmer you can google for something like "avr isp" to get more information on programmers and how to get one.
AVRdude will not work without a Programmer, so you need your programmer to be connected to your development system and powered on to complete this tutorial.
