Need advice on creating facebook ads please?

For creating FB ads:-
Autism support group select reach as you want spread awareness about that.
Local PC repair business select store visits

I usually only run ads for traffic, engagement, video views, lead generation or conversions--none of those seem to fit what you're doing (except possibly engagement).

If your PC Repair Business is an actual brick & morter shop in which you want customers to physically walk in the store, you could go with "store visits;" however, I don't think that's a good idea because you're limiting yourself to people who are having computer trouble at the moment they see your ad. Therefore, it might be better to try "local awareness" even if you don't have a physical store and it's just you making housecalls.

But, I think a much better idea would be to set up a lead capture page with some sort of relevant giveaway (and, run it only to those in your town and maybe some nearby towns). That way, you could send them emails with links to helpful articles, and even throw in some affiliate promotions for software, etc., and always mention your service in your signature.

If you go with that idea, you'd want to run ads for "conversions" and you'll have to learn how to use the facebook pixel to do that, so you've got your work cut out for you.

As for the Autisim support group, the type of ad you run would depend on whether the group is a facebook group or a live, local group where you want people to physically show up at a physical location.

If it's a facebook group I would definitely run an "engagement" campaign designed to get people to join your group. If it's a physical address, I would again run it to people in your surrounding area and go with "local awareness" again. However, since I have no experience with "local awareness" please take my advice with a grain of salt.

Hope this helps.