Hi Rajat,
I understand that you want to use the switch block in your diagram.
To achieve your desired functionality, you can utilize a 'switch' block that takes input from both the 'S1' and 'S2' blocks. Depending on the state of either block, you can determine the output. For instance, based on your requirements, you can select the output of the 'Boost converter' if 'S1' is on, and the output of the 'Bulk converter' if 'S2' is on.
For more detailed information on how to use the 'switch' block, you can refer to the documentation provided at the following link: https://www.mathworks.com/help/simulink/slref/switch.html
Hope this resolves your query!
