Good question! Essentially, we are following the content from getgems.io, the largest NFT marketplace on TON. It suggests that we can use two specific addresses as dead addresses, similar to what we know from Ethereum:
By sending NFTs to these addresses, you will lose complete access to them, making it impossible to retrieve the NFTs.
It's important to note that there's currently no full-fledged "burning" or deletion of NFTs on TON as it exists on other blockchains. However, the plan is to add "burning" in the traditional sense to NFTs on TON in the future.