AIBU to suggest marketing or design training alongside acting work?

What ideas does he have?
I know quite a few actors and opera singers and, in my experience, these are highly determined and motivated people who don't need their mum picking a job for them.

Decent designers study for at least 3-5 years and build up experience, learning all sorts of skills and software. It’s bloody insulting to suggest he can just do a bit here and there because he’s ‘creative’ 🙄

Does he have qualifications on Spanish? Could he be an official translator for places like Big Word?
He could go pnto Fivrr (i think that's what its called) to set up as freelance creative.
I know i pay for social media management, copywriting as I value humans skills and not ai when it comes to representing my business

I don’t want to be rude, but he wants to be an actor so why are you pushing him into jobs that once he is in, he will not be able to nip off to auditions or even take an acting job if he got one. I would look at jobs he can work round acting which is why being a waiter is so popular. Carer on zero hours is another. If and when he decides to give up on acting, he can decide on his career path then. I am always surprised how few stay in the entertainment business at all. I am a nurse I have worked with many a nurse and admin who were actors, as well as models and one glamour model from the 80’s. Just tell him he needs a job and he can work out the rest if he is being lazy.

Bank work? It’s like supply teaching, you pick up odd days covering sickness etc. hopefully that’s what people mean rather than a proper full time role 😁

And you’d need a degree in nursing first.

Mr friends an actor, sidelines carpentry, beekeeping, gardening.

Sounds like the perfect all rounder

Most of the jobs you originally suggested will not let him just regularly duck out of the office for a few hours for an audition nor will they be terribly impressed if he asked them to hold a job open while he sods off to do three months of Ibsen on a tour. It's kind of insulting to people for whom jobs like that are their actual career to treat them like something one can just pick up and put down when 'proper' work isn't available.
Something that requires virtually no training, a short onboarding, and very little detailed knowledge of the employer's systems and structure would probably be a good fit. Something with transferrable experience, not just the old chestnut "transferable skills".

Indeed, but you have to...erm, qualify first

All the actors I knew (in London in the early 2000s) were also either temp database experts or PAs. Temp roles gave them the ability to take up roles and be more flexible for auditions.
While both will be hit by AI, there are still PA/reception/IT roles where a human is needed. A young relative is an AI trainer and is making good money (for now anyway). Ideally you want them doing something which can turn into a real job if acting doesn't work out.

Plumbing is very competitive to get into and I can’t see an established plumber wanting to take on an apprentice who actually wants to be an actor and skips off to auditions over someone who really wants to be a plumber.

But only after taking years out to train to be a nurse