From our home, it is about 15 mins train ride to all main attractions in Helsinki. our family's favourite place to spend time in Oodi, new national library with wow-architecture. https://www.oodihelsinki.fi/en/what-is-oodi/architecture/.
Near by is Museum of Contemporare Art Kiasma https://kiasma.fi/en/ and our Consert Hall. There is a nature reservation area quite near by. I also like to go somewhere by seaside, maybe do a bit island hopping from Market Square. From railway station i might take a bike and cycle to somewhere. https://www.myhelsinki.fi/en/info/quick-guide-city-bikes