Hi,
1 - If you do not need to send tax returns for 2021-2022 and 2022-2023 tax years, then if you have any income to declare, you can do this in writing, sending your letter to H.M. Revenue and Customs Pay As You Earn BX9 1AS.
2 - You must submit your whole tax return together and in the same format. This means you either submit a SA100 and SA109, along with any other relevant supplementary pages on paper or by buying a commercial tax return that includes SA109 and submitting that version of the return online, using your government gateway user ID and password.
3 - Under the terms of Self Assessment, we do not provide an official exchange rate and the onus is on the individual to use a just and reasonable exchange rate for each acquisition and disposal.
For your convenience, there are exchange rates at:
https://webarchive.nationalarchives.gov.uk/ukgwa/20231016190054
https//www.gov.uk/government/collections/exchange-rates-for-customs-and-vat and for older rates at: https://webarchive.nationalarchives.gov.uk/ukgwa/20100202113554
Exchange rates from HMRC in CSV and XML format
You are free to use any of the supplied rates or one of your own choosing.
Thank you.