Answer: It is correctly written.
Explanation: The sentece is "Estudio español desde hace dos años."
Where the speaker is talking about himself, so the person is "Yo" (and it is implicit ).
The conjugation of the word "estudiar" is in present time, this is correctly conjugated (Yo estudio..), because the talker is saying that he/her is studying Spanish since 2 years ago, so in the present, he/her is also studying it.
The rest of the sentence is written correctly, so the whole sentence is written correctly.
