I’d like to find out what level I am in Nigeria; we have 100 level, 200 level, 300 level, and 400 level?

The US education system does not follow a qualifications framework, unlike some countries. If you are asking about the level of our undergraduate degree program based on a qualifications framework of a different country, this must be evaluated by the Ministry of Education or a credential agency dedicated to reviewing foreign credentials for credential equivalency.