My 3rd gen camry is puffing a tiny bit of white smoke right now;been like this for 3 months, didn't really pay attention til now. Its the head gasket i believe. I checked it from the front, and saw a tiny bit of seepage on the right of the head gasket(may be something else). How bad is this? and what is the extent of the damage? I've had the engine overheat once in the past due to running on no coolant and just noticed that i've been driving the car with little oil

, and a decrease a in performance. I fear a warped head.
Do those headgasket seal products really work and if so how much are they?
I want to save my baby ASAP and my wallet.
My priority is the headgasket and then the 4 oil leaks i have. I've stopped driving her btw.