Why my phone is not turning on

@shwetamehta we need to know what exact model your phone is. We also need to know if anything happened to the phone prior to this. This sounds like a power issue but could be a firmware issue as well.

Try a forced restart: Press and hold the power button and volume down button together for about 10 seconds and see if your phone restarts

There are a couple of basic things that you want to check. First check your charger. Make sure it has proper output. Then check your charging cable. Check to make sure that the connectors are not bend etc. After that, check the charging port. Clean it of any debris etc, use a few puffs of air to clean it out. If none of this works, get a USB ammeter and see if your phone draws any amperage from the charger. If it does not, it is possible that this is a charging port issue or a bad battery.

Your Android phone or tablet has very few buttons. The only way you can turn it on is by pressing the power button — and that isn’t working. Don’t panic! Android devices may sometimes refuse to power on or wake from sleep when you press the power button, but your phone or tablet probably isn’t broken. There are some easy ways to make your device boot again.