I live in Pennsylvania U.S and I am paying a loan in Puerto Rico. Can I add those interests?

If you are paying mortgage interest on a primary or secondary residence you own in Puerto Rico, that interest can be deducted as mortgage interest in your itemized deductions.  Interest on a personal loan is not deductible.

What if you moved mid year to the US (from PR) but paid the mortgage the whole year, do you enter all of the interest paid throughout the year or only the interest paid while in the US?