Hi, Vladislava! 1) It will be better to say: "I am a fifth year student (at university)." Or even "I am a senior student" (American English), if the 5th year is your final year!) 2) "I'm studying at university" is fine. You are just highlighting that this is a temporary current situation in your life by using Present Continuous. Present Simple "I study at university" is just a fact about you. Which would also be correct.