Questions about how to use API

i tred to make the App. to close the add banner(kill the banner) under Yahoo messenger chat [login to view URL] resize the screen..with API someone plese tell me step by step to do this start from the begining.i got the code to closing yahoo 5.5(1229)attached . ## Deliverables Complete and fully-functional working program(s) in executable form as well as complete source code of all work done. Complete copyrights to all work purchased. ## Platform win9x ## Deadline information must finish by 9/17/2002