I earn income from YouTube which is taxed monthly before reaching my account from the United States. I've been told I require a foreign tax certificate for filing a tax return. Which article of the country's Double Taxation Agreement covers the income in this request? I do not visit he US to earn money there, I remain within the United Kingdom. it also wants me to specify how much I earnt, however this is a very hard question to answer, the sum could fluctuate between £10k and over 100k a year given so many variables, what am I supposed to do?