"The Village Blacksmith" by Henry Wadsworth Longfellow doesn't really go into detail about the work of the blacksmith, because readers would have been familiar with it. Especially before mass production became common, the blacksmith would have been responsible for making and repairing most metal goods used in a village.
The typical process began with placing a metal bar in a special type of kiln known as a forge. Bellows (air pumps) were used (often operated by apprentices) to keep the interior temperatures of the forge hot enough to soften the metal. The smith would remove the softened metal from the forge using long, heavy metal tongs and place the heated metal on a flat surface called an anvil. The smith would then use a hammer and files to shape the metal. This was dangerous and difficult physical labor.
Blacksmiths made and repaired most common metal household and farm implements, including shovels, axes, plow parts, needles, and pots and kettles. They also made weapons for soldiers. Many blacksmiths also made horseshoes and would shoe horses.