YOU SAID:

I thought I was good at games until I ate chicken

INTO JAPANESE

私は鶏を食べるまで、私はゲームが得意だったと思った

BACK INTO ENGLISH

I thought until I eat chicken, I was good at games

INTO JAPANESE

私は思った私は食べるまで鶏、私はゲームが得意だった

BACK INTO ENGLISH

Until I thought I would eat chicken, I was good at games

INTO JAPANESE

まで鶏を食べるだろうと思った、私はゲームが得意だった

BACK INTO ENGLISH

Until I thought I would eat chicken, I was good at games