Engine cranks but will not start after overheating

My car was overheating so I pulled over. It's boiling over in the overflow tank so I wait a while (with the car off) and check the fluid level in the radiator it was low darn near empty. I look under my car and there is a big puddle under there it was antifreeze called up the tow truck driver he came out and cranked it and cranked it for 30 seconds each time (with no coolant in the tank). I finally told him he's going to mess up my engine then it made a horrible noise and shook like crazy then just wouldn't turn over. So I had him tow it and I replaced all (16) the spark plugs and the gap size on each plug were different and 2 out if them were smashed to a.000 gap with what looks like burnt oil on them. No smoke out the cars exhaust, no milky oil, but it was low and looked like it really needed to be changed. After changing the plugs it cranked just fine but won't start.