Connect your Arduino board or the MCU you want to use as a modchip, to your ISP programmer that you just created, following the schematics. I introduced this test because even if avrdude tells you ...

Contents presented in the Microcontrollers Laboratory Course; Microcontrollers used: Arduino UNO R3 & DOIT ESP32 DEVKIT V1 - CSE Department, Shiraz University, Spring 2025.