I see you're in Accra, beautiful place, I've been to the Golden Tulip several times.
Concerning your question, the answer is, it depends. It depends on factors like what your expectations are, the school you attend, your grades, area of practice and of course who you know. In general terms, I think that being a lawyer provides plenty of opportunity to earn a decent living in most parts of the world. The best ways to increase your earning potential include, studying hard, pursuing a career in an area of law you're passionate about, getting out and networking with others in the industry and not being too proud to take a low level job after law school to gain experience.
Hope that helps.
In the United States, the average lawyer earns about $80.000.00 per year. Could be lower or higher depending on many factors. I can attest that it's challenging work and I earn every fee I receive from clients.