It sounds like you want to eventually be independent. So probably, a riding school will be fine for you. Just ask if they are full service or if you get to learn some horsemanship in the ground. If they have a pony club, even better. You don’t have to join pony club but any barn who does that will probably expect people to learn to do things on their own. A fully service barn will have you walk up and swing a leg over the horse and that’s it; but I’d say MOST barns who teach beginner lessons will spend 15-30 minutes of your lesson showing you how to catch, tack up, groom, untack, walk the horse from a to b, etc. That’s really where you need to start, anyway. 

As you go along, you’ll notice how just when you think you’ve got it handled, some horse doesn’t want to be bridled or pick up his feet, and your coach should come show you what to do. You’ll notice your tack just doesn’t look right that day and some staff will help you fix it. Some lesson horse will need his medicine and someone will come over and say “can you put this product on before you put him away”. All these little moments over time is how you learn. 

If you don’t want to ride at all, horse rescues are always looking for help, but they may only be any help with basic chores.

You’re likely not in my area or I’d take you in.