Int.on housing loan

My friend have taken residential flat
by taking housing loan from bank.
In his tax return he claim housing loan interest deduction u/s 24 & principal loan instalment payment
deduction u/s 80C
Now he wish to give his residential flat on rent & he will take another
house on rental basis for own livin, , , , g purpose.

My question is as under
1) Can he claim housing loan int.part
& principal instalment part as deduction

2) Is his income from rented house
wants to be added in his income from house property.

3) Is he claim rent paid HRA deduction u/s 10(13a)
You are requested to guide us