I hear this mistake all the time, so I thought I should put it down here.
In English we say “news” not “a news”. It is uncountable.
Vanesa: “I have some (good/bad/strange) news to tell you/share with you/for you!”
Rob: “Really? What’s the (good/bad/strange) news?”
Vanesa: “I’m pregnant!!!”
So please do not say “I have a news” or “a good news” – okay? Just say “news” or “some news”.
More example sentences:
“Hey, did you see the guy on the news today that won the lottery? he looks so happy!”
“I heard on the news today (meaning TV or radio) that Toyota is recalling a lot of cars.”
“My co-worker shared with me the secret news that our company is down-sizing again. I wonder if I’ll survive the chopping block?” (That means stay working and not get fired)