Burning the bootloader in the ATMEGA328P

Just finished building a emonTH from scratch and the next step is to burn the bootloader in the ATMEGA328P chip.
From what I read, the only way to do this is using the ISP pins and a programmer - a raspberry pi in my case.
I need a confirmation about the ISP pinout - one of the pins have a little line next to it and I assumed that is pin 1. Correct?

If you have built it from scratch, you must have designed and done the drawings for the PCB, so why are you asking here? We do not have any details of your design.

ATMEGA 328 chips with an Arduino Uno compatible bootloader already burned into the chip are available from a fair number of sellers. Are you sure yours is not one of those?

I purchased it from Farnell and assumed it doesn’t have a bootloader.
After I saw your post, I checked to see if I can upload a scketch using the USB to serial UART adapter and the upload failed.

A Google search for “arduino burn bootloader” comes up with this as the first hit:

You will need to check the datasheet for the chip you bought to work out which pin is which on your chip.