* "Deux ans" means "two years" in French. It's a noun phrase.
* "Je suis" means "I am" in French. It's the beginning of a verb conjugation.
You wouldn't say "deux ans" on its own, just like you wouldn't say "je suis" on its own. You would use them in sentences:
* "J'ai deux ans." (I am two years old.)
* "Je suis heureux." (I am happy.)
Let me know if you need help with anything else!