What does that mean?
"but keeping a low profile because of threats to his life."
I mean obviously, I get it with the context. But I am not entirely sure as to how I can use these two phrases on my own
When "profile" is being used as a noun, the phrase is almost always "keep a low profile". It's usually used when somebody is looking for you, often somebody that it would be really bad to have a problem with, such as the police or the Mafia, but it could also be used for mundane situations like avoiding an ex-girlfriend/boyfriend.
"Low-profile" and "high-profile" can be used as adjectives with a similar but distinct meaning. In this case, "high-profile" roughly means "well-known" or "highly publicized", and "low-profile" means "obscure". Something that's "low-profile" might indicate that there may be something suspicious going on, for instance, a low-profile deal between a business and the Mafia, but that isn't necessarily the case. I don't see these terms used very often, but they'll be understood.
I hear "keep a low profile" quite often in news; it usually refers to a public figure (not necessarily a baddie) who wants to remain inconspicuous.
I am a non-native speaker and let me give you a good example.
For example, if you have a problem in passing your mathemathics paper and you have been failing it over and over again and you are not able to get your degree because of that paper. You hire a good friend of yours (he is a whiz at maths)who is agreed to sit(through illegal means) in the exam in place of you and have cleared your paper. He would probably say to you: "abc, keep a low profile about this whole matter." so that other students might not hear about it and pass it on to the higher chain of the school.
Another good example is. If you and your friend have sex with your class mates without your parents' knowledge- Both of you would like to keep a low profile on this whole suspicious activity of yours. (It means you would not like to talk with your other buddies about it )
Profile is someone's life and character. If you keep a low profile, you avoid doing things that will make people notice you.
Angelina Jolie has a high profile status. She is the most beautiful and versatile actress in Hollywood. She earns a lot of money. She is not an average Diana. So wherever she goes, whatever she does, photographers and journalists will be following her and publishing her every single move in the newspapers and magazines. In a word, she is a high profile figure.
I hope that helps.