I am currently working on STM32F207ZG Nucleo-144 Board. I have changed its IP but I want to store this IP in permanent memory. How can I access its permanent memory such that when we reboot it, it stores the changed variables.

[Piranha]

Well, compiled constants are in permanent memory and are restored after reboot...

But, if You mean configurable parameters, then start with AN3390:

https://www.st.com/en/embedded-software/stsw-stm32061.html