New to UK taxes - Double Taxation Relief and Self Assessment

I am a UK Tax resident with uk income that is taxed automatically (I work in a school). I am will also be receiving freelance(self employed) income from the United States. They will require me to file and pay taxes on this. As this will be my first time doing taxes in the UK I am unsure if I will be obligated to pay taxes on this income in the UK. I am also having trouble understanding the taxation agreement. What are my UK tax implications for my foreign income? Are they zero as long as I apply for the tax relief? Is there a certain amount of foreign income I can make untaxed by the UK? Any and all advice is welcome.

Hi Brittney,
You will be liable to declare the income in the UK but may be able to claim Foreign Tax Credit relief for any US tax deducted.
Please refer to guidance here:
Tax on foreign income
Foreign tax credit relief and capital gains (Self Assessment helpsheet HS261)
Thank you.