In this visualization created by The Guardian, we can see how North Korea compares to South Korea in terms of population, Gross Domestic Product (GDP), life expectancy, freedom of the press, military spending, internet connectivity, infant mortality, among other indicators.
North Korea is a poor country with half the population of South Korea. It is one of the worst countries in terms of corruption and freedom of the press. Its military spending constitutes approximately 22.3% of its GDP, compared to 2.8% for South Korea.
Additional resource: IndexMundi: South Korea vs. North Korea – Country Comparisons
If north korea really go for war than it will not exist after war and than there would be only one Korea i.e. South Korea.