Sure, for books I recommend the "for Dummies" series of books on anything electronic. Some hobbyist electronic stores have all sorts of books and magazines you can get too (idk the name of any stores outside my country though, you'll have to look what stores in your country have that kind of thing. Those hobbyist magazines and books are what I learned from.

Online there's all sorts of stuff, a quick google search for me found a lot of good stuff on soldering and electronic components . Those "for Dummies" books are really good for the theory and math behind all of it. Also your local electronic shop might even have "learn to solder" kits you can practice on, they usually explain what all the components do and why you're making the thing. You can even find really cute custom ones on etsy if you want.

If you want to get started solderless, give arduino a go, they're really cheap and there's all sorts of projects that are fun, and/or useful, and you can even get your kids involved in many of their learning projects. Definitely pick up a kit (or a clone kit from AliExpress), it's lots of fun, and you learn some programming too.