How to Read the ESP32 Internal Real-Time Clock (RTC) - Arduino Tutorial 

HI Guys,
Welcome to this tutorial on using the internal Real-Time Clock (RTC) on the ESP32 microcontroller. The RTC is a low-power clock that runs independently of the main processor and can be used to keep track of time even when the main processor is in deep sleep or powered off.
In this video, we will go through the basics of setting up and using the ESP32 internal RTC. We will start by showing you how to set up the RTC module by configuring and setting the time. We will then demonstrate how to read the current time from the RTC and how to set alarms and timers using the RTC functions.Here,there is no need of external RTC.