A level choice confusion Watch
It is definitely possible to do 4 subjects. I personally did 5 A levels in Year 12 with Maths, Further maths, physics, Chemistry and Biology. Don't be put off by what RAB2018 said, what I think they are saying is that it depends on the person? I didn't find five a levels ridiculous to be honest but I have decided to stick with 4 by dropping biology because I wanted to focus on admissions tests preparation. I had 5 A* predicted grades anyway though.
Hope this helps!
Dm me if you would like to ask for anything or for study advice.