Was it running before you began this work? Chances are something is not reconnected or broken that was removed to get to the head. Reheck everything you did. Plug wires on right plugs? Injector wires on right injectors? Got any spark? Pull plugs and check compression. Raw gas on plugs means flooded condition. lol
The approximate cost to change an oil pan gasket, on your Ford Taurus, is $125. The oil pan gasket can be purchased for $10.
The 2001 Ford Taurus has ( 2 ) head gaskets for each of the V6 engines that are offered from the factory
cacked head, or (luckier) head gasket, try the gasket first.
On a component like that gasket goo is always a good idea. Coat it very evenly. My preferred goo for these kinds of jobs is "Permatex Aviation Form a Gasket"
Get a shop manual. This is a complex procedure.
Change the head gasket.
I'm not a mechanic / technician but on a 2004 Ford Taurus if you have the 3.0 liter DOHC " Duratec " V6 engine you would because it has a timing chain going to each cylinder head
The Ford Taurus for the most part has a V6 engine. It has 2 head gaskets. Some very early model Taurus's had 4 cylinder engines which had 1 head gasket.
A gasket seals something (fluid, air, dirt) in or out.
There is only one fix. Remove and replace the gasket. This is a major repair that should only be attempted by an expert.
ballpark $1500 sight unseen
There are two head gaskets,one for each head.