A-Levels vs IB, I need urgent help

Hi, thank you all for your help. I have to choose now either to go to IB or A-Levels (I’m going to year 12 now). To give you all context, I want to go to an American University, I am a strong student but I have a bit of problems with deadlines. I am a very good student across all subjects, so I want to go to the system that helps me achieve the best grade possibles. So I don’t know what will help me more, as although doing great in only 4 subjects (A-levels) seems easier than 7 (IB), I fear being burned out by only doing 4 subjects and perform worst. Also I’m worried about the daily life un both systems, as I have heard that IB is so stressful, but helps you get better grades. I really don’t know which, and need your advice. Also I come from igsce, so IB would be new, though I don’t fear the change. Thanks.