You have several options. You could use your current qvw workbooks as data source using binary loads. That does mean you need to keep Qlikview around to reload those documents. Then next step is to convert the load scripts from the Qlikview workbooks to Qlik Sense. You can do this using Qlik Sense Desktop. You can them import the resulting Qlik Sense apps in Qlik Sense Server. You can also copy and paste the script from a Qlikview document to a Qlik Sense app and make the necessary changes yourself. This will be mostly changing the connections to the sources. Connections to files and databases is handled differently in Qlik Sense. Connections are created and added to the library. Then in the load statements the connections from the library are referenced. Apart from that the script is almost completely compatible. You can find the unsupported functions here: QlikView functions and statements not supported in Qlik Sense ‒ Qlik Sense
I once did this and it worked.
I took one of my qvw files saved a copy of that and dragged and dropped it on it the Qliksense desktop top, all the edit script is converted accordingly with only minor changes like Lib and connections.
Even I got a qvf file but be careful before dropping qvw file on to Qliksense desktop, save a copy of it.