1993 Ford F-150 Car will not run unless I am pushing the gas

Engine problem
1993 Ford F150 V8 Four Wheel Drive Automatic 120K miles

My truck will not stay running. I turn the key, and sometimes I can get the engine to roll over, but when I do, I have to keep my foot on the gas, because it will not idol. When I take my foot off of the gas, the truck shakes and sputters down and turns off. There is something leaking under the truck, it is a pinkish tint. I checked the oil, and it is fine, and there is plenty of gas. What could be my problem?