Hi @dipak.acharya,
You can show the contents of the current issue under the journal homepage by checking the “Add the table of contents for the current issue (if available)” checkbox under Journal Management, step 5.
You can enable browsing by categories under Site Administration, though I’m not sure if that’s specifically the same thing you’re looking for.
Beyond that, you’ll probably need to work with the OJS 2.x code.
Regards,
Alec Smecher
Public Knowledge Project Team