https://github.com/nostr-protocol/nips/blob/master/09.md

Read the spec. Even relays that choose not to implement Nostr, eventually drop all content. 

Delete is a core part of Nostr and it works. Don’t trust trolls who wish Nostr didn’t support delete.

nostr:note178tfxt6r98e4huv5d8vv7u8x0nkhclt0whcep3z8xutu9uuj4yuqf7syk6

Edit works in some apps: nostr:note1te9fy33mg6jax8krp8wwvlh7acagh60q0ylmkunmhzwc5f4kugqqlzsky3