1. Yes, you will have to do the Life in the UK test if you apply for a British passport. The language test is only obligatory if you don't have an English qualification which shows you have a strong knowledge of the English language. Here, if you don't have formal qualification, I would suggest you speak to someone in the language department of your University of Sussex and get a Cambridge qualification certificate in English. Be aware additionally, that you will need to have a Permanent Residence card for one year before you apply for a British passport based on five years residence in the UK. Here is a link to a page on the UK Government website which explains how to apply for one https://www.gov.uk/apply-for-a-uk-residence-card/permanent-residence-card. This requirement is essential because you have to be able to show you were visa free for one year before you get citizenship.
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