I have a project to do for school at macroeconomy and I want to know if it's correct to talk about the unemployment rate of a county(if this is micro or macro economy).
As the previous answer correctly states it is macroeconomics. Just let me add more detail.
Microeconomics, studies the decision making of individual agents in one market at a time.
In macroeconomics we also study behavior of agents (e.g. representative consumer, firm etc) but we do it across multiple markets.
If you would study only employment at a market for fast food workers that would be microeconomics. However, when you do that for a country as a whole (which counts unemployment in all formal markets) then you are doing macro.