Hi Nolan, If you are not a European citizen, but you are an official resident of Europe, you can choose to use an Interrail Pass. We ask for your country of residence when you order, so you will need to bring an official European residency card or document along with you that matches the country of residence written on your Interrail Pass. All information about this topic can be found here. 

If you have a non-European passport, you can also choose to buy a Eurail Pass. This has the advantage that with the Eurail Pass you can travel freely in the UK as well. If you choose to purchase an Interrail Pass, you can only travel through your country of residence (in your case the UK) during 1 inbound and 1 outbound trip. More information about this rule for Interrail Passes, have a look here. 

I trust this answers your question. Cheers,