getting this error when trying to boot off external ssd,An error occurred while setting “Samsung SSD Boot” as the startup disk: The operation couldn’t be completed. (SDErrorDomain error 108.)

As far as I know, booting of an external drive into Windows is not possible on a Mac. The virtual environment may boot if its virtual image is stored there, but that's only within the virtual environment.

Also you need to make sure your external drive is formatted APFS to be able to boot Mac OS using Disk Utility.

And to run the installer of the OS on the external drive from recovery or internet recovery to get that installed on the external drive. There has been some difficulty actually cloning all the information from internal to external drive including the boot commands that I've seen in Monterey even on an Intel MacBook Pro 13". Once I ran the Mac OS installer on the external drive, it was able to boot just fine. Just make sure you use the same or newer installer than the original data that was cloned over.

What model Samsung SSD?

How is it connected to the Mac?

Have you previously installed any of the Samsung software?

Also, what is your need to boot off of an external drive? If to is purely for data space, you are much better off keeping apps on the internal SSD and moving most if not all of your data to the external drive. There are many articles available for setting up tings like Apple's Music library , movie libraries, etc,. on an external drive. FWIW, this is how I have my system set up. I keep all data possible on an external drive and use very little space on my internal drive. This also makes it easier when replacing a computer or even sharing that data with another computer. Simply unplug it from one and plug it into another.

One last note, sometimes the new Macs can be a bit fussy about the external SSD being used to boot from. Thunderbolt SSDs seem to be the most reliable and USB based SSDs can sometimes be problematic. Sometimes USB SSDs will boot just fine on one M1/M2 Mac model but not another model and sometimes even identical models.

I'm having this issue as well. I have a Samsung T7 1TB. Also using Apple Silicon M2 Mac mini with the 256GB.

Even if you re-route all of your files, there's still a ton of system data that eats up the internal 'drive'. So I wanted to see if I could create a boot up drive/external Mac OS. I'm a long time Mac user, and making a boot up disk was much easier in the past. After making the drive AFPS compatible (Couldn't do it with Ventura, had to use my intel based Mac Pro running Sierra to do that), I got as far as installing Monterey on it. And it booted successfully. But the M2 Mini would not recognize it, so I tried installed Ventura on it, from the M2 Mini. Several times in fact. I got the error the original poster received.

So I guess I'll just reformat and call it quits. I'm thinking this Samsung drive probably isn't Thunderbolt 3 or whatever compatible(it uses USB 3.2), making it useless for a boot drive. Should've just bought a 512GB or higher. Not liking where Apple is going with their systems. My mistake for getting the low end.