1.1 IDE (2.1 Hello World)
Here are the links and files you need:
Arduino IDE, we don´t work with it directly, but we need it. (We only need the avrdude. exe and avrdude.conf.But you need the version 1.8.19. With the newest version 2.x it doesn´t work!)
Microchip Studio IDE, (former "Atmel Studio") the best IDE to program the ATMega328P with, I think.
To unite Arduino and Microchip Studio. It´s written in German. But there are pictures explaining what to do. (But you need the version 1.8.19. With the newest version 2.x it doesn´t work!)
And here is the first Program. You have to extract the ziped file by right clicking on it and choose "extract all". When you start "Atmel Studio" and open the solution, it might be, that the program doesn´t open from itself. Then please use the "Solution Explorer" on the right side. If it´s not present you will find it under "View" in the tool bar.