Mac Mini Late 2014 upgrade to Samsung EVO 860 1TB SSD + Mojave clean install

Hello,

I've replaced the former HDD from my Mac Mini Late 2014 by a new SSD Samsubg EVO 860 1 TB.

I don't need to clone my former HDD Mojave + BOOTCAMP partitions. Instead I want to setup a clean Mojave on this new SSD from a bootable Mojave USB key that I've prepared as well.

The issue is that when I start my mac with the new SSD inside while maintaining the option keyboard key, I can't see it in the list of disks my new SSD. Instead the mini boots directly on the USB key and later propose me to setup a new Mojave mac os. When selecting this option, again my new SSD do not appear.

I was wondering if I should "prepare" somehow the new SSD (connected as an external drive) under mac os (which is still on my former HDD) before doing the hardware replacement? Like formatting, creating partition, ... with the disk utility?

Thanks in advance for your help on this question.