Ford cougar 1999 started overheating and water tank gets empty quickly. I drove it for 10 miles, smoke came out and car lost the power, then could not start afterwards. I noticed some oil leak on the floor. I topped up water but flushed out immediately with some oil. No mixing of oil noticeable on dipstick. I changed water pump but water will not stay in.

Its under the throttle body near the coil pack