Please Help!

Hi! I found out I was pregnant with my son Last year in September. I hid my pregnancy from the father & just kept my pregnancy lowkey. I don’t know how to explain to my ex that he has a son.. The reason I didn’t say anything until now is because I was scared of his reaction & if he was going to flip out completely. He’s a college student, who works & also does other stuff during his free time. & here I am… my inducing day is June 15th. How do I tell him he has a son on the way without scaring him away ?