Best teeth products for whitening that don't eat away the enamel?

So I have cavities in my two front teeth that may have to be root canalled. The One tooth is worse off than the other and the holes are in the sides probably due to not flossing but they are embarassing so i am getting them filled with white filling to look normal again. The problem is I need to whiten them so they don't fill the filling to match my teeth when my teeth are not very white. This will be a problem later when my teeth turn whiter but not the filling. I need to buy whitening products such as tooth paste and maybe white strips and mouth wash that arnt harmful to my teeth so when i go to the dentist in a few weeks my teeth will be white so they can match the filling to white teeth. What products can I get to whiten my teeth fast and arn't very harmful?