Time limit on entry for greencard? Need advise please.

[Markysparky]

When one recieves their greencard, how long do you have to physically enter the USA if still based in a foreign country?

I mean how much time would I have to enter the US if I recieved my green card today? A month, year, exactly how much time is allowed?
Im asking because I want to finish my studies in my current country before moving to the USA.

[MaryH]

Six months to year. You can call to confirm. I'm sure it's not more but in the ranges given.