Hi,
If you qualify for split year then you only report any foreign income for the UK part of the year.
RDRM12000 - Residence: The SRT: Split year treatment
If you do not qualify then you will need to report all your foreign income to the UK.
Tax on foreign income
The guidance at RDRM12150 will help you work out if split year treatment applies.
RDRM12150 - Residence: The SRT: Split year treatment
HMRC cannot advise you on which case this applies under as it is up to you to determine this based on the guidance available. You cannot file online if applying for split year treatment as the SA109 is not compatible with our system. You will need to file by paper or buy commercial software
Thank you.