The blockchain is a distributed ledger technology that is used to securely and permanently record transactions. It is a decentralized system that is not controlled by any single entity and is resistant to tampering. Transactions are verified and confirmed by a network of computers, and once confirmed, they are permanently recorded on the blockchain. This makes it virtually impossible for someone to alter or delete a transaction once it has been confirmed. This makes the blockchain an ideal system for recording any kind of transaction, and it is increasingly being used in many different industries. So, to answer your question, once a transaction has been confirmed on the blockchain, it is permanent and cannot be altered or deleted.
