Is transaction time correlated to block generation time
On average, based on Bitcoin protocol, a block takes 10 minutes to mine.  Transactions that optimize miner profit take precedence in the block. In other words, the transactions that pay the highest fee get incorporated into the block first and therefore get confirmed the fastest since currently the mempool is large. The mempool consists of all transactions that are waiting to be mined into a block. A transaction that pays a low fee can be stuck in the mempool for a very long time if the mempool remains crowded, so it’s hard to say how long a particular transaction can take; but, yes, a transaction that is broadcast to the network remains unconfirmed until mined into the blockchain.