Do I enter Box 27 of my T4RSP or do I leave it empty as this amount is not taxed as Income

on profile do I say yes to HBP repayments

Yes, enter the amount shown in Box 27 of your T4RSP. This  amount will not be included as income and will have no effect on your tax return itself, but it needs to be entered for CRA records and determining your repayment schedule.