Hi there Omniben!
You might find the 'Typical Engineering Entrants' box at the bottom of the 'Entry Requirements' tab of this page useful. I think it's worth noting that 95% of our entrants who were taking A Levels between 2017 and 2019 had Further Maths. That's not to say that you couldn't be successful without it, but statistically, only 5% of our entrants are.
If you want to apply, we would recommend you take AS Further Maths if you can. Any additional mathematical studies which strengthen your mathematical abilities will help, both with preparing for the Engineering Admissions Assessment, and with the transition to studying Engineering at any top university.
We'd also recommend not pinning all your hopes on getting into Cambridge. You may turn out to ace every part of the application process, but in reality, the large majority of our applicants don't, even the ones who are ultimately made an offer. Even if you had the most compelling personal statement and are the most interested applicant we've ever seen, this won't compensate for mathematical and physical problem solving skills. Working on these by strengthening your maths is probably the most important thing you can do to make yourself as competitive as you can be.
Hope this helps!