23 years old looking for a room/apartement in Stockholm for two years

I'm going to attend a Master in electic power engineering at KTH. I'm looking for an apartment or a room in the city center or at least I want the possibility to move by foot. If it is possible I would like to have a room on my own while I'm avaiable to share the kitchen and the bathroom. I also want the possibility to visit the apartment before the payment.

I'm quite open-minded and I have no preference on the kind of rommate I wil have. I would prefer not to be alone in Stockholm and at the same time I would like to share the apartment to someone not too reserved.