Housing Erasmus Student - Finding accomodation after arrival?

Hi! I’m a 20-year-old student coming to Barcelona from February to early July for an Erasmus Semester at UAB. So far I haven’t had much success finding a suitable room in a shared flat through websites (Idealista, Badi, Faceboo-Groups,...) either bec. of insane prices or scams which makes me unsure whether to keep trying online or to book a hostel/Airbnb for the first 1–2 weeks and search once I’m in Barcelona in February. I would like a place somewhere near the S2 Line (e.g. El Farro, Gracia, Eixample) as I will need to commute almost daily to UAB.

My main concern is arriving without a place and not finding anything quickly.

For those with experience: Is it realistic to find a room after arrival in February? Any tips for getting viewings for shared flats once in BCN?

Thanks!