When i turn on my heater,steam that smells like coolant comes out and fogs up my windows.I have been told it's my heater coil but i don't know hoe to fix it...any suggestions will help!!!

Its not too difficult to replace the heater core on the early Explorer models. I had a Ranger pickup with the same dash, and replaced the heater core without a lot of trouble. Here is a link that shows it:

http://www3.autozone.com/servlet/UiBroker?ForwardPage=az/cds/en_us/0900823d/80/0b/9b/39/0900823d800b9b39.jsp