What is the difference between STM32CUBEIDE and ARM Mbed ?

I will be buying STM32F401RET6 to learn Embedded C programming and maybe use the evaluation board into future projects. I am also studying from NPTEL(online lecture series) basics OF ARM CORTEX architecture. In the later course, they are teaching programming on ARM Mbed platform.
Another Udemy course Instructor is teaching on STM32CubeIDE. Now I am very confused?

Are you buying a bare chip or an evaluation board? The e-board is much easier to start with.

It's an evaluation board.