There are limited options to use loans to finance a university education in the USA if you are a British citizen.
Eligibility criteria can be found online for the UK government's Professional and Career Development Loans.
UK banks will be able to offer personal loans, but you will have to begin making payments during your studies and interest rates are considerably higher than a student loan.
If you are a US or dual US-UK citizen, you can apply for US federal aid through the FAFSA website.
If you do not hold US citizenship, you might be able to take out a private loan if you have a creditworthy US citizen or permanent US resident who can co-sign the loan agreement with you.
Some graduate school financial packages will loan money directly to international students. This will be clearly indicated on their website.
We recommend you seek independent financial advice before taking out a loan to fund your studies.