It is assumed that you are currently tax resident in the UK. If your annual rental income is in excess of the £1000 property allowance, you may wish to consider claiming the remittance basis. If your total unremitted foreign income is less than £2000, the remittance basis is automatically applied, and no further action is required.
If your total unremitted foreign income is in excess of £2000, and you decide to claim the remittance basis, you would have to register for Self Assessment (SA) and claim the remittance basis in your SA tax return. You can see information here:
PIM4410 - Property allowance: contents: overview
Remittance basis 2021 (HS264)