I learned to touch type at a young age, using a book my grandmother used to teach herself:
https://www.etsy.com/market/gregg_typing_manual
Put your hands on asdf and jkl; and just start typing random combinations of those letters without looking until you know what letters/fingers to use. Then you gradually expand, first to g and h, then to nearby letters in the row above and below, then to numbers and symbols.
Some other tips:
- don't smash the keys; practice using as little force as necessary, because the impact at the bottom of the key travel is going to cause finger strain
- use right ring finger for the backspace by twisting your wrist slightly. Don't use pinky because you either have to stretch it or move your arm. I use left ring finger for tab for the same reason, although it's closer and pinky is not horrible
- don't worry about keeping all your fingers on the home row when reaching for numbers. It's better to move your hand a bit, for example, to press 1, rather than stretch your fingers. Or you can curl your fingers and move your hand up. If you feel your fingers stretching/straining, it will cause fatigue and/or carpal tunnel.
- you just have to commit to spending time to learn to touch type. You can start by using your thumb for the spacebar, not your right index finger!