I'm just short of 50 and can probably give some answers to those questions. I'm sure there are folks even older who can go deeper.

before computers, how did you learn to do something?

Books and other people. My father taught me a lot of basics around home improvement. I spent several years in auto-shop in high-school. I used to read a lot of things, just to satisfy my curiosity. Honestly though, the internet has made this sort of thing much easier. You're far more likely to find information on what you want to learn. However, you're also able to find a lot of bad information. And most of social media was a bad idea.

Did access to knowledge change your life, was a constraint lifted when you no longer depended on having found the right books or people to learn tips on how to cook a new dish, or how to fix a plumbing problem, or how to plant a garden?

Can't say it "changed my life", but it's certainly a much better situation. Though I will say that the internet and easy access to information is still no substitute to having someone on hand to teach you for many subjects. Just the ability to ask questions and get immediate feedback is invaluable. Especially when analyzing your screw-ups. Having someone there to talk though what you did right and what you did wrong and how to avoid those mistakes in the future just can't (currently) be replicated by Youtube videos. Still, I'd much rather have the internet than not.

Was life more simple, did you have fewer problems to solve without technology in your life, or did technology make life easier?

It's a mixed bag. Part of the "life was simpler" is just the rose colored glasses of nostalgia. There wasn't the constant barrage of information and distractions. However, if your local library didn't have the books you were looking for, you were up a creek. At the same time, I think there was more opportunity to fix things and tinker. When toys, bicycles and cars aren't 90% semiconductors, you can actually pull out a set of hand tools and fix a lot of stuff yourself. On the down side, being a nerd or just being different led to a lot of bullying, with most authority figures basically telling you to "suck it up". Not that I'd condone it, but I sort of understand why some kids turned to violence. So, as I said, a mixed bag.

Oh and adjacent to the access to information, the access to stuff is still kinda amazing. Sure, it's easy to hate Bezos and Amazon. But, the fact that I can click on an item on the internet and it shows up at my door a couple days later is fucking amazing! I would ride my bicycle to the hobby store and hope they had any interesting D&D books. One time, I even got the owner to special order a book for me, which was a bit of a disaster. It's really hard to explain how fantastic it is to just pick a random item out of millions and it just fucking shows up in days. Like, what even is this magic?

TV watching is also so, so much better. While I do sorta miss the Saturday Morning Cartoons ritual, I like not having to time my life around network schedules or setup a VCR timer and hope it works correctly this time.

So ya, overall I think things are better now. I'm just waiting for all that really cool tech like cybernetics and flying cars which is supposed to show up in the distant future of 2020.