Help !!! ASAP please

White smoke from the exhaust is a sign of burning engine coolant due to a leaking cylinder head gasket. Your mechanic can perform a simple chemical test at the radiator to verify that.

Not loosing coolent, the smoke coming out of the exhaust smells like gas and car waisted a quarter tank of gas in a matter of 5 minutes checked for gas leaks and there is none, but it seems gas is coming out of the exhaust

Excessive fuel usually makes black smoke. To go through gas that fast, probably the best suspect is a leaking fuel pressure regulator, but I don't know if your engine uses one by the engine. If it has one on the fuel rail, remove the rubber vacuum hose going to it and check if it's wet with fuel inside. Replace it if it is. I suppose an injector could be stuck open too but that would not be common, and I don't think it would use fuel that fast.