Try Keybr.com or Monkeytype right now, they're free and they actually work really well. The difference from what you probably found before is that these don't make you learn boring exercises - they give you real-time feedback on speed and errors, and the game is addictive enough that you end up keeping at it without getting tired.
Finger placement is fundamental, yeah, but it's not rocket science. You just need to make sure your 8 fingers are on the home row of the keyboard (ASDFGHJKL) and your thumbs stay on the space bar. After one, two weeks max of daily practice (like 15-20 minutes), it starts becoming automatic. Not perfect yet, but your brain starts absorbing the keyboard map without you looking at it.
Realistically, to go from two fingers to decent speed takes about 6-8 weeks if you practice consistently. I've seen people make insane progress in less time just because they didn't give up after a week. The trick is not to push crazy speeds at the start - focus on accuracy, speed comes on its own once your fingers know where to go without thinking about it.