They don't contain cyanide per se. Peach seeds, apple seeds, cherry, etc have a compound called amygdalin, which breaks down into hydrogen cyanide when ingested. It would require quite a lot of seeds from each that would probably need to be ground down and consumed at once to get anywhere close to a lethal dose.
I'm sure somewhere there are guides, but it isn't going to be exact. Cyanide can be effective and swift at the right dosage but it is not recommended, it can be pretty painful and not as quick as we would like.
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