Yes and no. "Talents are our lives' guiding destinations." The above sentence is grammatically correct. All the necessary parts of speech are there, in the right forms, and in the right place in the sentence. It's even correctly punctuated. However, there's one major problem - the sentence doesn't really make a lot of sense. A destination is a place, and a talent cannot be a destination. There is also no such thing as a 'guiding destination'. As a phrase, it means nothing. 'A guiding xx', such as 'a guiding light', is something that takes you to a destination - it cannot refer to the destination itself. You need to rethink the sentence entirely. Do you mean that our talents help us to achieve our goals in life?