This may be a dumb question but where would one learn about first aid?
Well, I picked a good bit up just from helping my mother and father patch up myself and my siblings after various scrapes and bumps over the years.
But, I am also a security officer. My company paid for me to become first aid and CPR certified.
I went to actual classroom classes. But the American Red Cross offers online courses. ( http://www.redcross.org/take-a-class/first-aid/first-aid-training/first-aid-online )
I would recommend going to the in-person classes if possible, simply because they have demonstrations and you can practice on dummies and suchlike. But the online classes are good too.