Not everyone in the church can be an elder. Only those qualified can be appointed. Even then, there must always be more than one of such men. In some congregations, no male members are qualified to be elders. The men of the church then must take care of the business matters until they grow and develop enough for elders to be appointed.
Deacons are also to be appointed to serve under the elders.
They are known as servants. They are to work under the direction of the local elders. Likewise their wives must be reverent, not slanderers, temperate, faithful in all things. Let deacons be the husbands of one wife, ruling their children and their own houses well. Now this is the divine organization of the church.