22 year old girl looking for accommodation in Napoli from April to August

My name is Joséphine, I am a master student in genetics and with my studies I have the opportunity to do an internship from the beginning of April to the beginning of August in Naples. 

I am looking for a nice student appartement, big enough to live comfortably for 4 months. 

I will do my internship at the TIGEM institut which is located in Pozzuoli so I am looking for an appartement close to a station from the line 2 metro. 

I like to go out and also to visit so it would be perfect if the appartement is located in the center of Naples. 

Finally I am searching an appartement with a second bed or a convertible sofa so that my mom can come visit me. 

If you think you have an appartement that fit this criteria don't hesitate to contact me.