<<Can I deduct the interest on my second house? Do I have to declare a house as the principal residence?>>
Yes, you can deduct the mortgage interest that you pay on a second home.
No, you don't have to declare it as your principal residence in order to deduct the mortgage interest.
https://www.irs.gov/publications/p936#en_US_2018_publink1000229900
**Answers are correct to the best of my ability but do not constitute tax or legal advice.
