Firstly - architecture in the UK is a design based degree. Universities expect to see either a creative design based subject (art, design, graphics etc) or a portfolio of artwork and drawing (or often both). Your choice of A levels isn’t bad but it will mean you will have limited support creating a portfolio and little free time to work on your art in your free time.
Secondly- uk universities don’t offer full scholarships to international students. Some universities have a handful of partial scholarships covering some of the fee costs but not living costs. Particularly for architecture which requires 5 years of study in total to qualify - you are unlikely to find any funding available.