As is. I'd like to make a keyboard that correct specific word automatically, but I don't know where to start.
Can you guys let me know what and how to search?
There is no way to do this programmatically. And there is no "Android keyboard", any OEM can ship any keyboard he wants as the default, and the user can override that choice. A specific keyboard may allow you to do this, but there's no API for it, it would have to be done by the user (and how would be off topic here).