I WOULD NOT recommend replacing the Apple factory-installed SSD with a SATA drive (even if it's possible).
Reason why:
SPEED.
A SATA SSD (2.5") will "max out" around 600MBps.
The factory SSD is MUCH faster.
Download Blackmagic Speed Test (free) and post the numbers it gives you RIGHT NOW, with the factory SSD.
Are you just "running out of space"?
Then there are other, BETTER WAYS to "get more storage space".
Something like the Samsung t7 "Shield" in a 1tb size, plugged into one of the USBc ports on the back, will become "just what you need".
Yes, you will have to get used to "managing" where stuff goes, with two drives on the desktop.
That's trivial. You will master that within 3 days.