Atemga328p-pu error when burning bootloader

I'm new to arduino. I've been trying to program my Atemga328p-pu. I've seen the other forums and most of the issues are coming from those using an Atemga328-pu, not Atemga328p-pu. For a few days now I've been facing this error when trying to burn the bootloader:

avrdude: stk500_recv(): programmer is not responding
avrdude: stk500_getsync() attempt 1 of 10: not in sync: resp=0x03
Error while burning bootloader.
avrdude: Yikes! Invalid device signature.
Double check connections and try again, or use -F to override
this check.

I've been following this youtube tutorial:

I've checked all of my connections, and they are all correct. Do you have any suggestions for my issue?

Furthermore, when opening avrdude.conf I see that the signature is set to Atmega1280 on one part of the doc, and then set to other Atmega numbers...how exactly should I edit the whole conf file so it matches Atmega328p-pu? Or better yet, can anyone give me the link to download the correct avrdude.conf for Atmega328p-pu?

Thanks in advance
Michael