What do I absolutely need to use (and keep in mind) for online privacy?

I only really know the basics about metadata, VPNs, and the fact that your phone is basically a walking tracker. I get that if you want true privacy, the answer is just "don’t use electronics lol"

But I also know that abandoning technology entirely is counterproductive these days. So… what should I actually use and keep in mind? I’ve heard Tuta isn’t trustworthy either