Hi Mahendran,
During sleep, the motherboard is typically powered off (S3), so the Internet will not work.
In S0, standby, there might be a possibility that the Modem is powered on but there is no guarantee that Internet works.
I hope this information helps. If you have any more questions, don't hesitate to reach out.
Otherwise, please take a moment to rate the answer. Wishing you good luck!