You will need to take the residence tests to determine your tax residence status and whether split year treatment applies (RDR3 Statutory Residence Test
If split year treatment applies, you claim it in a self assessment tax return (SA100 & SA109) but do not include this foreign income.
If split year treatment does not apply and you are resident for the full tax year, you will need to report the income and tax deduced in your tax return and claim a
foreign tax credit for the overseas tax paid.
Tax returns and supplementary pages can be found at Self Assessment tax return forms