Where did these platforms invest? From where does it get content sources?

It pays to the producers. Suppose, any movies come to the theatres then OTT platforms talk to the producers to stream them on their platform. They take the rights from the producers by paying them. So, here, these platforms invest and get the content source. They buy online streaming rights from the producers.  Buying a complete movie.  Secondly, it invests to get a complete movie from the producer. Like, in pandemic we have seen that ''Dil Bechara'' has streamed on Hotstar directly despite theatre. So, these platforms buy the original movie from the producers by paying a complete amount for the movie.  Making and investing for own movie In these platforms, we see such as amazon originals, NetFlix originals, etc. In such streaming, these platforms invest themselves in the movie. They prepare the content and work accordingly.  Some OTT Platforms in India Amazon Prime VideoNetflixDisney+ HotstarVootZEE5LYCA TVJIO TVHOI CHOIBig FlixHYFLIXSony LIVMX PlayerALT BalajiEros NowArreSun NXTShemarooAirtel XstreamAdda TimesVIUVodafone PlayTVF PlayMUBI