¿Cómo se dice "say" en español?

My spanish teacher said this to me.. look at the ending on your verb. you need to make it agree with "yo" this is my sentence- sí yo estudiar español en la escuela how do i make it agree with "yo"

The teacher didn't explain this at all and i don't understand this

2. choose the answer that best completes the sentence. tú (entregar) los libros. (2 points) a : entrego b : entregas c : entrega d : entregan