Miyajima - Osaka - Okinawa

Hi there
Looking at travelling from Miyajima to Osaka via train, then fly to Naha (Okinawa). Where can I find train times and durations so that we can work out corresponding flights.

Just trying to plot this out as to how long it will take and the cost....to work out if it's viable or if we increase our stay on Miyajima / Kyoto and Osaka.

Thanks so much.

Kristen