There are lots of books, but a lot of “ordinary” women won’t do the complete regime as practised by beauty professionals - not unless it’s for a really special occasion, anyway.
For example, I don’t use thousands of different applicators. Fingers for almost everything, really. I do use a blusher brush or sponge, and of course, mascara always comes with a wand (though I don’t always use mascara anyway).
If you want a really high definition, “glamour model” look, then I suppose you should buy, use, and regularly clean all the correct tools, but most of mine are lying unused, as fingers are so much quicker and easier, for everyday.
Also you do not have to buy the most expensive, luxury brands to get a decent result. I still swear by cheap basics like Rimmel and Boots No. 17. I find picking the right shade is far more influential on the finished results than how much you paid for it. A flattering shade will always look good, even if it’s a supermarket basic, but paying ten times as much won’t compensate for a colour that just wasn’t the right choice.
Of course, it’s worth asking your wife how she would do things, if she still could. She needs a look that’s natural and normal for her. If she wouldn’t normally go about with fake everything, then you need to look at replicating what she would normally do - not the “extreme makeover” look you’ll see in some videos.