I plan to deposit $8000 into an RSP and then immediately transfer that to an FHSA in February 2025. How would I input all this on my 2024 tax return

If you make an RRSP contribution before March 3, 2025, this would be entered on your 2024 taxes. But if you make a FHSA contribution now, this will go on your 2025 tax return, as the FHSA goes by calendar year. Your T4FHSA slip will show the amount transferred from your RRSP.

This Canada Revenue Agency (CRA) page has more information about transferring between RRSPs & FHSAs: Transfers into your FHSAs