It means you really got a jack pot or a big chance! in a positive sense! Eg: Wow Man!! I remember the day you got a big break with your awesome performance !! Hope this helps :)

you got a break/you get a break It is slang that describes someone showing you mercy. "The cop did not give me a ticket, he gave me a break." "Wow, the cop did not give you a ticket? You got a break."