My son could read the alphabet and recite it at 18 months. He learned this on his own because someone gave him a kid's alphabet book and he kept pointing to things in it and we'd tell him what they were. I think kids are perfectly able to do this stuff by 2, they just need to be exposed to it. For the record, we didn't encourage this behavior or try to push for it, he just really obsessed over that book for ~1 month for some reason.

He can't read. He can identify letters but not words. He will spell out his own name written down but have no idea it's his name. He can type with index fingers. Ie. He's memorized where the letters on a keyboard are.

Is it common? I don't know. He's probably just marching at the front of the parade right now.

Learning ABC (especially with pictures), being able to recognize them, counting to 10, pointing out letters on a keyboard are all easy enough for my 2yo. Can't do arithmetic or touch type, if that's what you're asking :-/

Basic letters and digits aren't too crazy if they have a sufficient environment for it - e.g. materials/attention from parents for learning.

My mom's a kindergarten teacher (and has been to some rather low-income schools), there's kids who have essentially never been spoken to and struggle behaviorally and academically and haven't really even seen the alphabet.

At that age it's essentially all about their environment.

My two year old knows the alphabet and can count to 10. She can't type but only because we never let her play with tablets or phones.