Applying for Undergraduate Architecture at MIT or Cambridge

Hi, I am a Lower Sixth student in UK and I have always want to apply for architecture undergrads. I am doing IB HL maths and arts at school. I'm particularly interested in biomimetic, responsive architecture inspired by mechanisms in nature and I am doing projects related to this. I got 1500 at SAT but wish to take one more SAT and try SAT2 if coronavirus would allow me to. I know MIT application is intrinsically difficult and Architecture at Cambridge is particularly hard as its ratio is 12:1, but I still want to give it a shot. I currently do many service, projects and activities at school, some related and some are not related to architecture, including environmental committees, debating, mun, architectural society,etc. I do not have much experience of doing maths or physics competitions, is it necessary or particularly helpful for me to put hard work into academic competitions for applying an architecture degree at highly academic school like MIT or Cambridge? Or do they value more the art portfolio and projects I do? As coronavirus has disrupted many exams, how should I prove my academic skills?