user37085: How do I burn the UNO bootloader onto ATMEGA328P-PU without using an Arduino Uno board. That is burn directly from my PC or Android device??
I've tried nothing, I don't know a thing about microcontrollers ☺

user1576: The short answer is, you need a AVR programmer
It is a tutorial on the Arduino website:
https://www.arduino.cc/en/Main/Standalone
And the section Bootloading your chips OPTIONAL will answer the question.

37085: <p>How do I burn the UNO bootloader onto ATMEGA328P-PU without using an Arduino Uno board. That is burn directly from my PC or Android device??</p>

<p>I've tried nothing, I don't know a thing about microcontrollers ☺</p>
 1576: <p>The short answer is, you need a <strong>AVR programmer</strong></p>

<p>It is a tutorial on the Arduino website:</p>

<p><a href="https://www.arduino.cc/en/Main/Standalone" rel="nofollow noreferrer">https://www.arduino.cc/en/Main/Standalone</a></p>

<p>And the section <em>Bootloading your chips OPTIONAL</em> will answer the question.</p>
