Yeah it's cool. I went through the same thing of having to learn all the heroes, just wanted to warn there is a steep learning curve, but it is worth it if you like that type of the game.
You can go to playdota.com and click on the guides to learn more about each hero and the thought process that goes into choosing items. Once you know that, you'll know how to do your own builds or adapt to other people's item builds.
Im like a pro in respect of stratergy games, You know when you just realise what your good at and not,Don't if its just me,Well il try learn how to play that just got to put effort together with time