If you go into debt/owe money to the bank etc. they used to send you a letter in RED print to warn you! Some companies still do it... so if you get a letter IN RED, oh dear! You owe money or are overdrawn at the bank. So IN THE RED is not a good state to be in! You have little money, or no money! If you are famous and IN THE RED you'd MAKE THE HEADLINES. The newspaper would have a big headline, maybe on the front page, saying, "FAMOUS ACTOR GOES BROKE!" (goes broke = has no money) If anything makes the headlines it is an important event that people want to read about or see on the TV news.

"To be in the red" means to be in debt. "To make headlines" means the story was all over the news/tv/internet and usually everyone knows about it. Hope that helps! :)