Delete/insert/update SQL DB using c#/subsoinic

Question

the problem i have guys is im really new to this and trying to understand it all still, i currently have a web service complete and working in vis studio 2010,  the service lists films that are in an sql db, the problem i have is i need to add some function to it to be able to delete a film from the list, insert a film to the list and and update function too

i have to be honest i dont know where to start can anyone help me here?  :)  :)
 
i have enclosed a .rar file with my project in