I got lucky since I've been into computers and programming since I was 8 years old (late 90s). My first job when I was at school was a part-time developer at a tiny IT company that did consulting work. Since then, all my jobs have been software development jobs.

The fact that it pays well in places like Silicon Valley was a great bonus. I moved here 10 years ago (when I was 23) after I got a job offer, and the starting salary was literally double what I was getting paid in Australia at the time.

The job changes a bit as you get more senior - there's more mentoring of junior devs, project planning, deciding what your team should focus on, etc. I still spend a lot of my time writing code though, and still enjoy it. :)

There's some downsides to living in Silicon Valley. A lot of stuff is expensive (that applies for California in general, but especially here). Housing is extremely expensive too.