Is a 12.6 handicap decent for 9 holes? I just started golfing last year and was wondering where I stand currently.

Like... More than bogey a hole. But I mean beginner! Practice and I'm sure you're on the right track.

its not bad for 18 holes

You played one year. Its not that bad at all.
Just spend time on the course and you will see yourself improve alot!

go to the range alot they day before you golf and work with every club and your bag. Dont just take your best club and swing it a million times