Connections for bootloading a nano based board

I am laying out a pcb based on a Arduino Nano, so it has SMT Atmega328 and the FT323RL. I am a little confused as to what connections I need for bootloading the chips as they will be blank obviously.
Can they be bootloaded through the USB port or do I Have to have access to MOSI, MISO and SCK just for bootloading?

Need SCK, MISO, MOSI, Reset, Power, Gnd for bootloading. Not USB port.

Obviously, all of those pins except for reset are used for other functions so you would most likely have access to them anyway. It’s convenient that they are brought together in the six-pin connector but it’s not essential. You just need some sort of header on each of those pins that you can connect to. Reset also.

If you are laying out a PCB with permanent connections to some pins, bear in mind that low-impedance loads on the pins for MISO, MOSI, or SCK can prevent communication through these pins for burning the bootloader.