Upon joining, a citizen picks which virtual country he or she wishes to join. Each of these countries is named after an actual country in the real world, and is generally located similarly (warfare may cause certain regional displacements). The citizen then seeks employment at a company within that country, and is allowed the opportunity to train as a soldier for that country. Training, and working at a company is done on a daily basis. One of the main drawing points of the website is that it takes a mere "14 minutes a day" to participate.
So according to the official "about me" from eRepublik, I think that they are doing it wrong. I am an eCitizen of Republic of Macedonia (fyrom) which does not exists in real life. The country's name is North Macedonia as per Prespa Agreement with Greece.