You can make it by speaking to Robin at the Carpenter's Shop. She'll require 100 gold pieces from you, 100 stone, 10 clay, and five copper bars. The silo takes up a three by three space on your land, so you need to make sure you have a location set up before requesting the structure.
The silo is a good choice as a first building to be purchased. It takes fewer resources to build than other buildings, and allows a good stock of hay to be gathered before actually having to meet the needs of any animals.
Cutting grass with a sword or similar weapon does not provide hay: only a scythe will stock the silo.
Since all grass dies in Winter and farm animals will entirely rely on hay for the whole season, it's advisable to cut as much grass as needed to fill the silo(s) near the end of fall, even if it takes all the grass left on the farm.
Instead of buying multiple silos, hay can be stored in a chest (when received as a gift in the mail from Marnie or withdrawn from the Hay Hopper before a Coop or Barn is fully upgraded). Hay can be moved from the chest to the Silo when necessary.and also you need bricks and hay
