Urgent Pls

Hiii

One of my friend got housing loan from bank. And my understanding is principal amount can get deduction from 80c & interest can claim from Sec.24(income from house property):- My doubt is

   (i)In Form No:-16a where should i show interest on housing loan as deduction.( if interest on housing loan shown as deduction in form no:-16a he will come under below tax slab)

                                      So please clarify ths as soon as possible.