I don't think there will be jail term for holding or mining, but trading they can impose, because holding or mining there is no way govt can find we are doing this.
For trading if you have enough crypto, you can go outside India and sell there and back to India and pay taxes on crypto earning.
But Bangladesh have the same punishment for holding the cryptos as well,maybe they don't know how to find the holding but if it happens in somewhat there will be some kind of punishment if that rule exist.