News means information or reports about recent events. Is it wrong if I say "I heard a bad news."? Yes, it is wrong. You can say, 'I heard some bad news.'
Information is always without (s); then how can I say many information?? 'much infromation' or 'a lot of information'
Sometimes we say 'many pieces of information.'
Is it wrong if I say "There are many information still missing" Yes, it is wrong. See above.