In need of legal advice not sure where to post

I am a student in the US from another country here on a visa, trying to earn my masters. I dated a dangerous man and am I now trying to keep myself and my family safe. I would like to report my ex boyfriends dad for being a drug lord in order to keep myself safe. My question is, will I be able to and can I be protected by the police. I have some valuable information only I know. I do not have many friends here nor know very much about the legal system. If anyone can provide some advice I’d greatly appreciate it !! I know this is odd to post but I am very anxious and do not know where to turn to

Thank you ladies of Glow!!

Edit:

Also how do I go to the police?