Hello Santosh K Tiwari,

I think the best way is to combine theory and practices. So, I suggest you to attend the some courses on Theoretical Chemistry on/and Quantum Chemistry.

Whike doing that, try to read some articles on DFT calculations on graphene and similar system. While reading, it would be helpful to try some tutorials on how to build related models and running calculations on some properties.

Here is an example of tutorial: https://docs.quantumatk.com/tutorials/exploring_graphene/exploring_graphene.html

Good luck

Dear Prof Godefroid Gahungu

Many thanks for your help& suggestions