(Contemplation) I want to try teeth whitening.

I want to try teeth whitening, but I don't have anyone around me who has done it, so I have no one to ask. ~ You know that your teeth can stain even when drinking coffee, right? That's why I heard you should use a straw ~ In summer, I drink iced Americanos with a straw so they don't touch my teeth, but in winter, I don't use a straw for warm drinks, so they tend to stain more. ㅠ There are also DIY whitening products available online and on home shopping channels, but I'm hesitant to buy because I don't know if they are trustworthy. ㅠ