Load the bootloader in an ATMEGA328PB

Hi Arduino likers

I try to bootload an ATMega328PB with my Arduino UNO in ISP but I don't know exactly the way to follow. (the files to use)
Is there somebody able to explain me the procedure .

Thanks

I suggest that you install the MiniCore core. Then you pick the options from a menu in the boards section of the Tools menu, connect the programmer and hit burn bootloader.

Hi groundFungus
This GitHub guide is very well made. (GitHub.com/MCUdude/MiniCore)
I did exactly the procedures and I 've at last managed my project.
Thanks a lot for this invaluable advise
Michel