What to say when applying for a job?

Im 17, ok so my friend told me to apply where she works (harbor frieght) because im looking for a job so i can move out, but the thing is its not like the posted the job, so what do i say, i walk ing smiley and happy and say "hi can i speak to the manager?" then what "heres my resumee? or do i ask for an application? help? thanks!!