But there is something I still confused. I don't know how to use the map editor. I want to create my own map so bad. I know the basic control like moving and placing blocks But I don't know how to paint etc.
True, a lot of things are not very self-explanatory, sorry about that!
I am working on an interactive tutorial for the next version which should become available soon. Until then, please check out this video tutorial (understandably, it's less interesting when it's a video):
Thank you for taking the time to make maps!