Hey @Arijit kumar8,
You can transfer your mutual funds online through CDSL, it can be done through the ‘EASIEST' platform. To know how to register on EASIEST you can check out this article29. Once you have transferred your Mutual funds to FYERS demat account, you can place a pledge request.
PS: Kindly get in touch with your existing broker where the mutual holdings are kept. As the procedure may differ from broker to broker.
Hope this clarifies!