@vladas, Okay. Thank you for your patience as I’m sure I’m starting to get annoying. That’s not really what I want to do, but I don’t know otherwise so I’m thanking you. Based on your suggestions, I have downloaded copies in PDF format of both the NomadBSD AND FreeBSD handbooks. Given that the FreeBSD one is over 900 pages, it looks as if I’m gonna be at this for a long time. If you don’t hear again from me, this is likely why.
Also, since you mentioned the speed of drive, I went over to the NomadBSD Handbooklet page and saw that they also recommend a USB 3.x drive. And they also specifically state to stay away from cheapie drives like the Energizer one I’ve been using. So, I’m also going to order a fresh new USB 3.x drive, SanDisk brand from their store on Amazon as there’s no other brand I know of that’s a known name in that space. Doing that will eliminate any possibility that my flash drive is at fault. I have not yet created an account to use the FreeBSD Forums. I’ve been trying to keep my mind off the NomadBSD thing and focus on something else less demanding for a bit since difficult and confusing things give me issues with my bipolar disorder.
Thank you for assuring me that Balena Etcher is the “correct” app. I don’t understand why that stupid image on my current flash drive is read-only. Maybe you’re right about it being that I’m in single-user, I don’t know. I’m just confused and feeling lost. I get aggravated when things don’t just work. And that’s not a good state of mind to be in. So, in order to preserve as much sanity as possible, this is on the back burner until I can create some time in which to read those two handbooks and get a better handle on what’s going wrong with my NomadBSD image. I don’t really like things that seem like a lot of slow, tortuous work. I prefer quick things I can do in a few minutes’ time and this ain’t it. I hate sounding like I’m lazy or unwilling to learn. 
But, this is where I am now.