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It all comes with practice, lots of it. Even 3 years into typing for me has gotten me to an average of about 60 WPM. It really takes a lot.

Just practice when you can. I haven't used a computer in over 8 years and I can still type 120 wpm.

Depends on what good means to you. 80 WPM and 100% accuracy is pretty good, that's where I'm at. If you want to improve, go with an accuracy mindset and try the gibberish letters from typing lessons and do numbers as well. I went from 80 WPM to 40-50 WPM because I'm not use to it. I will probably go from 40-50 WPM to 5 WPM if I try new keyboard layouts, but that is what makes you faster.

And take some break too.

I started typing playing computer games, and ended up at about 80wpm average naturally.

I then learned the dvorak layout along with perfect touch typing and now I am at 120+wpm average.

It depends on at what level you are right now, but a good starting point is to learn touch typing.

You don't need a alternate keyboard for fast typing, even if you see top typers get like 210wpm or something with a setup and a different keyboard. You can still be good without having to get all these things.