There are 3 things which must be done before you can begin smithing:
-Build a Smelter
Doubtless you already have a smelter, and it is likely that you have also found some ore and mined it, so I would have to guess that your problem is with fuel.
Fuel comes from two sources: Wood and Coal
-A Wood-burner will transform 1 wood into one charcoal
-A Smelter will transform 1 coal into 2 or 3 coke, depending on whether it's lignite or bituminous.
IMPORTANT NOTE: When working with coal, it takes fuel to make fuel. If you don't have any fuel to start with, then no options will be available at your smelter. Make some charcoal, and you can jump-start the process.