Hash that defines previous block in Blockchain vs mathematical solution Is the hash that defines the previous block (block A) in a new block (block B), the same as the hash the miner calculated to submit block A?

As far as I know, you need to find a nonce so that the hash of the entire block A starts with zeroes. If you find a fitting nonce is this hash with the zeroes used by the next miner in his block b when he links to your block with the previous hash?

To clarify, if person A found a nonce so that the hash of his block is 000231 is the hash in the previous field of the next block also 000231?

Thanks
Yes, it is. That is the hash of the block header, so it is used as an identifier for that block, and is used to reference it in the next block in the same way that a hash of a transaction (txid) is used to refer to that transaction.