Hello. Today I will show you how to upload code using FTDI module into ATMega328p-PU chip.
Step 1: (ATMega328p-AU) or (ATMega328p-PU)


This ATMega328p chip does not come with a bootloader, so you have to burn one on it. Also check my previous tutorial on how to burn bootloader with this link: https://www.instructables.com/Bare-Minimum-Arduino-on-Breadboard/.
Step 2: Upload Your Code

Now, we have the bootloader so we can communicate with the RX and TX pins and upload a code. For that, we need an FTDI module. Make the connections and upload your code.