For an IntelliChlor the ideal salt level is 3400. To start the season you want to be around 3600 to 3800. Lets take the middle of that range and aim for 3700. Go to the Pool Calculator, plug in 3400 as your starting salt level, 3700 as your target level, and add the amount of salt it says to add. Typically I round that amount to the nearest full bag, there is little point in worrying about half a bag here or there (unless your pool is quite small).
None of the salt related process has anything at all to do with your FC level.
For FC level you need to know your CYA level, look up your target FC level given that you have a SWG and your current CYA level. Then adjust the percentage setting based on your current level and your target level: raise the percentage if your current level is low, and lower the percentage if your current level is high.