how can I see ram usage status at the time of execute a code?
In colab, you can directly check on the upper right bar.
If you want to do memory profiling for a particular cell, then you should check out these magic commands:
For detailed info, you can check the implementation here : Profiling and Timing Code | Python Data Science Handbook
Do I need to call any module To use “%memit” this magic command?
Yes you need to install memory_profiler first. Refer the shared link