1996 Other Saturn Models iM stumped

This car has been through alot. I think I can fix it for dirt cheap. I think it has a chance to see 200,000 but I still have my doubts. The engine fan works intermittently which leads to overheats at stoplights and drive throughs. I also have a head gasket seep that is growing slowly but has not seeped into the engine oil. What is a cheap effective way to seal that without replacing it? My idle is bouncy when not in gear and the car sometimes shuts off. I have had trouble diagnosing that because it is also intermittent but I think it has to do with the overheats. Also, can silicone be used as a substitute for an oil pan gasket? Please help im running out of ideas.