Answer: "Yo voy a la farmacia luego"
Explanation: We need to complete the sentence:
"Yo ____ a la farmacia luego. "
And we need to complete with the correct conjugation of the word "ir" where the person is "yo".
The translation of the sentence would be something like:
"I go to the pharmacy latter"
The right conjugation in the present time of the verb "ir" is voy:
"Yo voy"
So the full sentence is:
"Yo voy a la farmacia luego"