Yes, JioPhone is a dual sim mobile phone. You can use one 4G sim card and one 2G sim card.
JioPhones comes with 4GB Internal Memory - so just like a normal Android smartphone, you can save as many contacts depending on the free space in your phone. In practial sense, you can store unlimited contacts.
Yes, JioPhone does support Live TV. You just need to select the channel, which you want to watch and hit the button "play".
Yes, JioPhone does have the alarm and Indian calander, too.