Hi Siva ,
1)Please go through the Qlik Sense Desktop-->on top of the Right hand side u can find (...)Menu click on that
2) and you can find the DevHub is an option.click on that
3)Now a new browser will open in IE/Chrome there you can find
4)Left hand side Tools Tab will have QlikView Converter click on that and select your already developed QVW application and it automatically converts all sheets into QVF.
and now you can see all Qlik charts in your .QVF file.
if any issues you find go through the below links
please close the thread if you got the solution