Hi,
You will only require expenditure to cover the income for the year.
The remain unused expenditure will be carried forward as a loss and utilised in a later year.
Ensure you complete SA105 in full.
Please refer to the following hyper link regarding the notes that refer to
Self Assessment: UK property (SA105)- and also the loss help sheet HS227
HS227 Losses (2024)
Thank you.