In the Collins dictionary, "ciclo" is translated as "stage" in the context of education. But "stage" would not have a clear meaning in UK education at least. Is it the same as "term" (trimestre")?
If you want to say something which would be understood in English-speaking countries, I recommend expressing it in terms of how many years you have been at university e.g.
"I'm in my fourth year of university / college."