How long did it take to get there? Would you have any tips?

I'm only at 125wpm

Great! Now how long did it take you to have a wpm of 125?

Well, I started using the computer at a very young age, so I was far ahead of my peers in terms of typing speed throughout school. I guess I was at about 60 WPM by the time I was 10/11, and I remember that I was at 80-90 WPM by the time I was 15 or 16. I got hooked onto typeracer during this time, and I went to 100-110 WPM in the span of a few months. I kinda quit competitive typing for a few years after that, though I did work a lot on the computer in the mean time. Recently got back into it and after a few tests, I found that my speed had automatically increased to 120-130 WPM. It's kinda hard to gauge how much time it would exactly take since I did have a lot of gaps in between and I never really put serious time into practice (I would only race for fun most of the time). But I would probably say about 3-4 years if you're already about 60-70 WPM and you put in serious practice.
I personally don't think I'm the right person to be giving people tips simply because I have really poor typing technique in general. I'm just way too used to it by now and that's why I can achieve the speeds I do. But I can tell you a few things I picked up along the way that helped me:
1. Get used to using Ctrl+Backspace to delete entire words. It comes in real handy.
2. Posture is actually really underrated.
3. Using 'Shift' instead of Caps Lock is way more comfortable and natural imo.
4. When you type out a quote, don't focus on a single word at a time. Rather, keep the entire sentence in mind. You'll feel it flows more naturally while typing it out.
5. Familiarize yourself with punctuation keys, to the point where it becomes second nature to you. I still see many amateur typists look down at their keyboard to find double quotation marks, numbers, square brackets, back slashes, question marks, etc.

Sup, check out my answer above.

I’m at 123 for my personal best.