Question

how can we say people is a resource

Answer 1

People as are source is a way of referring to a country's working people in terms of their existing productive skills and abilities.Human capital is in one way superior to other resources like land and physical capital, human resource can make use of land and physical capital.Land and capital cannot become useful on their own.

Answer 2

we can say that people is a resource as it modify all other resources and without it not any resource can be useful.