Loud noise coming from engine?

When I turn the engine on there’s a knocking noise. It started out subtly and I assumed it was my serpentine belt. Upon closer inspection, the noise is coming from the engine itself. I have no clue what it is. It started out sounding like when you turn a fan on and while it’s spinning you put a pen against the propellers. Now, it sounds more like a small metal object flying around inside a washing machine during spin cycle. I start up the engine and after about a minute it dies. Smoke comes out not sure exactly from which part of the engine and I can smell the strong odor of gasoline. I recorded a video to capture the sound and you can barely see the smoke if you keep your eye on the dipstick handle. Please help me.