Nigeria is strictly third world and if you have no experience in that kind of place, you may have some problems. If you have problems, there will be no one to come help. Your success there depends on your ability to adapt and survive plus live to a totally different way of life. They speak English, they understand almost none of it, and if they are telling you it, they are lieing.
You need to get paid in US dollars in the US before you work. Their currency is worth nothing outside of the country and for you to get money out is not easy either.
In short, if you have no military background, no experience in places like this, stay home.