Raspbery Pi SSD setup
Raspberry Pi 4
SSD + SATA-USB3 adapter cable *
Or use an m.2 SSD + USB3 nvme SSD adapter
to your SSD, the same as you would flash it to your microSD, plug it in and go.
You can follow the
official Raspberry Pi getting started guide
and just use your SSD instead of the microSD.
In most cases, the default 32-bit raspberry pi OS is ok, but if you have a pi4 or later, then
64-bit raspberry pi OS
is generally faster and worth potentially reduced functionality and stability.
* Certain SATA USB3 adapters are not compatible or are poorly compatible with raspberry pi, so check before you buy with the list in the guide below
raspberry pi usb boot guide
is very technical and detailed, covering a bunch of things you don't need to do, but also some details that might be helpful.