My experience is UK based so not sure how different things are where you are, and it’s also been about ten years since i was in that line of work. But for what it’s worth…
I was a draughtsman for about 5 years early on in my career. I worked for a consultant engineers (civil/structural). I’m not sure about other avenues but i would have thought that one of the more common types of permanent jobs for draughtsmen are likely to be, like mine, in the construction industry, either engineering or architectural.
Again, might be different where you are but over here it’s comon to be able to get into this line of work straight from school as a kind of informal apprentice. I started aged 15 with mediocre high school qualifications. I was allowed one day off per week to study at college part time. All my fellow students were the same.
Back then CAD was still relatively new and although i studied it i did all my actual work with paper, pens and razor blades.
However, CAD is really just a step up from the more advanced features of visio. In fact it wouldn’t be as efficient but you could pretty much use visio for the majority of draughting work, it just isn’t as powerful and flexible as modern CAD packages.
I was quite a natural for the role and my young age and lack of qualifications didn’t cause any problems. I really enjoyed it having aced at technical drawing at school. In fact i could easily have carried on doing it had the pay not been so lousy in the UK at the time. I have no idea about the pay where you are or what he would need to get in an entry position but it would be easy to find out.
It depends what kind of drawing he likes doing. If building plans are something he thinks he could get into why not call your local college and speak to one of the lecturers. Over here they were mostly former practicing engineers who decided to switch to teaching. Regardless i’m sure they will know what the story is for both salary expectations and qualifications.
To clarify one point though, i learned CAD in one 15 hour course. It’s not hard. The bulk of my training was not about drawing it was about what to draw, i.e. design principles etc. Engineering (and even a lot of architecture) is about maths more than drawing.
These lines of work can open pretty good career avenues. I’d be surprised if draughtsmen were generally huge earners, but here it’s common to start that way and through part time study and work experience move on to engineer etc.