I had my blood drawm and they said I had high chloride levels I am 21 and I do smoke and have for four yrs. What does chloride mean and is it bad?

Blood salts. Chloride is an electrolyte in our body that combines with others to form salts. Commonly it is associated with sodium to form sodium chloride aka salt. As a mineral in our body it helps with cellular function and can easily change with the amounts of hydration we have. If we are dehydrated for example we would expect salt levels to be higher than normal.
High Chloride. How high was the number and was it the only abnormal number. High chloride is a reflection of a body process, and is usually along with a high or low bicarbonate (sodium bicarbonate). But I suggest to get your labs done again. Could be a processing error. Stopping to smoke would be the single best thing you can do for yourself.
How high? Chloride is one of the components of the normal salts in our bloodstream (sodium, potassium, chloride and bicarbonate). Very slight elevations usually don't mean anything, but can be associated with being a little dehydrated. However, if chronic lung problems are present, an elevated chloride can be a sign that it is affecting your respiratory status, resulting in higher chloride. Talk to md/do.