I suggest changing to a keyboard layout other than QWERTY, such as Dvorak or Colemak. These are optimized to reduce the distance that your fingers have to move while typing, and increase comfort.

You can type all very fast with one finger. Just one simple trick: use different part of the finger, see? So for N, you would use the middle of the finger. Next for U, the top (well shifting your finger slight right) then middle again. Easy! With practice of course

Are you telling us to type with our knuckles?

Depends on how long your finger goes

Steps to type Number:
1. Index finger on N
2. Middle finger to U
3. Index finger to M
4. Index finger to B
5. Type ER in one step with Middle and Index on left hand

Hope this helps!

Alright, let me try... (I am 13 by the way.)

nunmber nubmer nubmer number number nubmer number nubmer number nubmer number nubmer number number nuumber number number number number number nubmer nubmer number number number number nubmer number number number number number number number number number number nubmer number NUBMER NUMBER NUMBER NUMBER NUMBER NUMBER NUMBER NUMBER NUMBER NUMBER NUMBER NUMBER NUMBER NUMBER NUMBER NUMBER NUBEMR NUMBER NUMBER NUMBER NUMBER NUMBER NUBMER NUMBER NUMBER NUMBER NUMBER NUMBER NUMBER NUMBER NUMBER NUBMER NUMBER NUMBER

See, you accidentally hit the "caps lock" key. This is bad because in the normal typing tests, that would count as 170 mistakes, since you typed each character as the wrong character. Next time, look at the screen so that you actually know what you're typing. This makes it less likely for you to send mistakes, since now you know exactly what you're typing before you click the "save" button on the message. And remember, even if you are 13 years old, it takes loads of practice for anyone to improve. Even those at above 100 WPM sometimes gets 92% accuracy, so even they are working on improving.

Although it may seem difficult, you are supposed to jump up/down the keyboard using the same finger to type words like number. If you throw another finger into the equation, it will probably just end up making typing even harder for you, since words that are positioned like "number" may get complicated in the future and your fingers may start getting tangled. Not only (with practice) will using the same finger result in much faster typing, but it's much less complicated than using two, as well. I can promise you, it will not a take a large strain on your typing speed by using the same finger (in fact, it will end up making your speed increase)- I use the same finger for typing words like "number" and I can type 130 WPM+. Don't worry too much about it.
+Side note- PLEASE do not use different parts of the same finger. Absolutely nothing positive can come from that. Just don't.

cleanest solution is to learn Dvorak or Colemak. I use Dvorak and it's much rarer to encounter into problems like that.

More jank solution is to just use middle finger for U. Back when I did use to type on qwerty I often typed Y with my left hand because words like my.

Everyone says to touch type but qwerty really isn't designed well for it to be touch typed, so if it comes to it I think breaking rules is fine on qwerty.