No need to do it at A level.
You might be able to become a lawyer in other countries. They normally have rules about what they require for you to be able to practice in their country. It will most likely involve taking additional exams. The law in some countries is a completely different system based, not just different laws.What you are required to do will depend at what stage of your training you are at. You dont mention a country, but you would need to contact whoever regulates lawyers in the country you are interested in.