It is reconmmened by the official visa website to buy dummy ticket.Read this for more info from the official schengen site https://www.schengenvisainfo.com/flight-itinerary-visa-application/
Don't ever try to do this thing. Embassy has now established a strict scrutiny of all the visa requests they are receiving.
Flight tickets needs to be booked in advanced and do not try to show a dummy ticket as they're going to perform a thorough investigation and if your visa gets rejected, they will mention the reason which may create problems for you in future if you want to apply again.
Better follow the standard procedure and have everything ready.
We tried to book dummy hotels, just because we wanted some more time doing our research for better accomodation, we cancelled all dummy hotels after week days after we got Visa. 3 days later, they called us and cancelled all granted VISA. :(
Please be careful.
No, you can't get a Schengen visa without a proof of flight booking. It is mandatory to attach a flight booking proof with your visa application elaborating your flight plan. You can attach a dummy flight ticket with your schengen visa application. This dummy ticket will be verifiable with six digit PNR code on airliner's website. Read more about dummy tickets. https://schengenflightreservationvisa.com/dummy-flight-ticket-for-schengen-visa/