When I start my Camry white smoke comes Out the exhaust and then goes away and there is a loud ticking coming from my valve cover that won't go away

the wht smoke is antifreeze leaking into the combustion syatem. A lower intake manifold gasket could be leaking or the head gasket. I am leaning toward the lower manifold gasket, because the leak stops. The headgasket is under pressure from the pistons and would cause the car to run hot if not overheat an dpush the antifreez up thru the overflow bottle. If you are handy enough you can tackle the gasket job, as it is above the head gasket and has to be removed to get to the head gasket. The ticking is sticky valve lifters. Mileage does come into play as well as how often do you change the oil? Try a can of engine flush and see if it cleans any sludge buildup out. If the noise still persists, then try another can. Do this before you tackle the manifold gasket. When yo do the gasket it is easier to get to with that out of the way, just take off the valve covers and you will have easy access to the lifters. Do check out youtube and be specific about what you are looking for. Also have the repair book handy for torque spec's, Haynes is pretty good but the shop manual is the best.