A student from Vietnam want to find out more about the GCSEs

Hello everyone, I'm a 14-year-old student in Vietnam who really needs help to find out more about the secondary-high school education program in England. I am looking for a scholarship to study A-levels in England, and after doing some research about the program, I'm getting more and more confused about it, mostly because of the GCSEs. I know that GCSE is a certificate that is required for all students who wish to take further studies like A-levels and IB, which is somewhat similar to a national high-school entrance examination that we have in Vietnam. That exam we have here is essential for 15-year-old students all over the country if they want to apply for a high school, and their grades are the standards to decide which school they can apply for. Therefore I wonder if the results of that exam can replace the GCSEs if I apply for a A-Levels course in England? If not, are there any certificates or qualifications that can stand in for the GCSEs? I really don't want to take 2 more years studying for the GCSEs abroad because my family can't financially support my studies for that long.
I don't know anything about this yet so please make excuse for my ignorance and please help and tell me everything that I need to know. I've been dreaming of getting a better education in England ever since I was a little girl and now is the time for me to find opportunities to make that dream come true.