Voice therapy/training/treatment products worth it?

I love karaoke, but my voice goes rough so easily. allergies, a cold, too much singing etc and I'm scratchy for a month. I'd also like to get better in general. of course the FB algorithm marked me and now I'm getting advertisements for all kinds of devices and trinkets and various tinctures and lozenges. anything actually work? any pro tips for fixing my voice otherwise? or is just basic practice enough?