The first COMMERCIALLY SUCCESSFUL was probably the Borchardt C-93, from 1893. Created by Hugo Borchardt.
Get a owner's manual from the manufacturer and follow the instructions.
The first semi auto handgun available commercially was the Schonberger patented in 1892 and on the market shortly thereafter. There was at least one semi-auto pistol predating the Schonberger, but it...
No, if it was designed to be a single shot, it's a single shot. It needs to be reloaded after each shot.
Yes, and there are many single action semi auto pistols out there. The M1911, for instance, and earlier examples of the Browning P35 Hi Power.