Vintage teapot safety guide?

Hello~
I recently bought a bunch of teapots at an estate sale, none of which have the names of manufacturers on the bottom. No matter how much I look though even when I find people or places selling them I can’t find whether they are safe to use or not, as well as if they are decorative or functional… Does anybody know of any books that go over vintage teapot safety, or what to look for to determine if your own is safe??
I don’t even know if this is a thing. I got a variety of types I got a brass pot, a silver pot, a ceramic pot with a warmer, and a pot that is glazed on the inside but the outside feels rough like stone or something?? I have ordered lead test strips, I don’t know how to tell glaze is cracked, I don’t see any actual chips taken out of anything, I don’t know what people mean by worrying about patina, I just like teapots and I really like using teapots and basically any advice you can give me would help. I don’t even know how to clean some of them because I know using acidic things can damage other things like silver or something seriously anything you can tell me is useful.
Thank you.