Why is my phone unable to switch on and it stopped charging as well

@knightdml try to force a restart and press and hold the power button for at least 8 seconds until the Android logo appears. After that you want to check your phone charger and your charging cable and see if that has the proper voltages as well as no bend/broke or corroded contacts. Check your charging port to make sure there is not debris in it that prevents proper charging.

Since this is a new phone, you do want to return it to wherever you got it from. It should still be covered under warranty and there should never be a reason to repair it yourself. Unlike good cheese, phones will never get better with age ;-)