can I store a big data size, like 100TB on ethereum blockchain? and then, is this mean that all clients should download 100TB to get full blockchain data!?
That would be extremely expensive.
1KB = 0.0128 ETH = $3.41
1MB = 13.1 ETH = $3,497
1GB = 13 421 ETH = $3,583,407
1TB = 13 743 895 ETH = $3,669,619,965
100TB = 1 374 389 500 ETH = $366,961,996,500
So I'm not sure if you can afford it ;)
You would lack the money doing. In theory, yes. But it would cost more than hell.