The Helsinki public transport system has been named the second best in among European cities, with a highly effective public transport system of metro, tram, bus and train lines, enabling the whole metropolitan area to be within reach. As a student, you get a discount on the public transport fares.
When the distance is between 5-7 km, biking is the quickest way to get around. Helsinki has 1200 kilometres of cycling routes, 730 km of them paved. About 500 km of them run in recreational areas and 90 km on waterfronts. If you don't have a bike, there's a great bikeshare system with over 250 bike stations with and more than 2500 bikes.
Helsinki has frequent flight connections to other European capitals, Asia and other parts of the world, and the Helsinki Airport is considered to be among the best in Europe.