Please ensure that you are the owner of the token before trying to burn it. You cannot burn a token you do not own.
A burned token will still appear in Studio.
Burning a token is the process of "deleting" a token from your contract. Be aware that even when you do this, you won't be able to use that token id again (e.g if you burn the token with id number 3 and mint a new token, it will have a token id of number 4, not 3)
Once you have burned a token, it will still appear in Studio. Once burned the artwork cannot be changed, if you would like to change the token artwork, it must be done before sending it to the burn address.
A burned token may still appear on the different platforms. If the token is owned by the NullAddress then it has been burned. If it still appears on a platform like Opensea you can request for the platform to hide this token.