What are the requirements for interview?

hi,im applying for a visitors visa to visit my bf from us...i am currently working but doesn't have enough savings but he ures me he will take care of everything...will this be ok to the us emby?and i haven't ask for my leave authorization from my employer, are the consul or the interviewer going to ask for it..?how long will the process takes?as i am planning my travel this last week of august.anyone could advise me...?thanks a lot i need information for this.