"I am calling my colleague."
Translation:Dzwonię do mojego kolegi.
"Przyjaciel" means "friend" in Polish.
To clarify the difference, in other languages the term "friend" is used more loosely while in Polish you won't call anyone you know a "friend" (przyjaciel). In Poland you don't have lots of "friends from school", you'll have "colleagues from school" (koledzy/koleżanki ze szkoły).
A friend (przyjaciel) would be a really close person you can tell things you wouldn't tell all your colleagues. Yes, you can have multiple people you'd call friends, but there is a difference there while in English it seems that everyone is a friend except for people at work - the word "colleague" seems to be reserved specifically for work-colleagues.