やっと映画館のポップコーンを食べられました！って英語でなんて言うの？

やっと- finally

映画館 - cinema

ポップコーン - popcorn

食べられました - was able to eat

やっと映画館のポップコーンを食べられました - I finally got to eat popcorn from the cinema もしくは I was finally able to eat popcorn from the cinemaになると思います。

I love the popcorn from the cinema, so I was so happy when I was finally able to eat it.

I love cinema popcorn, so I was so happy when I finally got to eat it.