Hello, oh civil engineering. I'm not too sure about CVE does specifically.
You can find out more from here:
http://www.eng.nus.edu.sg/cee/programmes/BEng_ce/CE-DegreeRequirement-20132014Cohort.pdf
Perhaps if you're undecided with what engin you plan to enter, maybe you can take general engineering before entering your second year.
Cos in your first year we'll all be taking the same modules (except for chemical, electrical engineering)
As you didn't take physics, you'll be taking a bridging module in your first sem before taking the engineering physics module in your second semester. I have a few friends who did really well and some who struggled, so I can't really say. While having physics background can be beneficial, most of us started from zero as we probably forgot after 2 years.
The first year is just teaching you the basics, taking more science and maths modules instead. You'll only take the engineering modules from year 2 onwards.
Maths is important because it is a means of expressing the theories that we learn. But I think A-level maths is harder though hahaha.
That said, while a physics and maths background will help, what is more important is hard work, perseverance and perhaps passion/dedication in what you will learn for the next 4 years.
I did struggle in my first year, wondering why did I take up engineering and not other fields of study. But over the course of time, I began to appreciate my study and I think I have no regrets taking up a B.Eng
Sorry if I missed out anything! Hope it helps and feel free to ask. I'll try to get back ASAP ahha