Ethereum established validator queues for entering and exiting staking to manage the rate at which validators can start or stop staking, ensuring network stability. The queues are in place because there's a limited number of validators that can be processed per epoch, safeguarding the proof of stake consensus. To know when your validator enters the active state, please refer to the under the "Wait Time" in the "Entry Queue". The wait time is constantly updating, depending on the current staking demand. Once your validator is active, you will start receiving rewards.