Bootable USB drive(s) created with balena etcher is "RAW" (not recognized). Help!

I'm using a 10+ yr old laptop w/ windows 10 (which may be the source of this problem) and planning to boot Linux onto a new Lenovo laptop. Anyway I downloaded Mint 21, verified the ISO file, downloaded balena etcher and ran it. All went well until after I received the "Flash Complete" message, and rejoiced that I had created a bootable USB drive. But jubilation was short-lived when I then began to receive MS's popups telling me I needed to format the thumbdrive.

Thinking that perhaps Etcher didn't like the original format (NTFS) or maybe the size or brand of the thumbdrive I'd used, I repeated the process with several other thumbdrives of varying other formats, sizes, brands - all with the same frustrating result. When I did attempt to reformat one of these non-functioning (supposedly bootable) drives - it wouldn't let me, claiming it was "write protected."

I'm thinking that the problem lies with this aging computer. I had trouble verifying the Linux ISO file because the version of Windows Powershell was an out-of-date one, stored alongside newer versions. Once I selected a newer one it worked as it should. So I'm wondering what other programs on here are also out-of-date. Windows claims that all the drivers are current, but they probably have a bridge to sell me too.

So at this point what I'm considering is finally plugging in the new Lenovo, doing what I did not want to do by signing into MS Windows, and going through the entire process of downloading Mint and Etcher and creating a bootable drive all over again.

Does this sound like a plan that will work? Thanx in advance.