Is there a way to download mp3 music files offline from wynk.in and Ganna.com.
Use idm (internet download manager)
Try UCMate (Android App) for JioSaavn Music Download
Iam not sure about Gaana as its a streaming platform, thus DRM protected
Yes, there is many ways to download. Like you can use the VidMate (https://www.vidmatehd.com/vidmate-pro/) app on your device. This application will help you to download videos for free.
Connect to VPN and use Deezloader. It is the easiest way to download music with metadata, album cover, et cetera.