Kyoto Station is huge. It is a giant complex with department stores, hotels, underground plazas, etc.
Both regular trains and shinkansen depart from the same station, making it one of the more convenient major stations in Japan. Out the front, there are connecting buses which cover all the touristy spots, and underground there is the subway that covers the rest.
Actually, I found the subway a bit useless. There are a few places that can only be accessed by subway, but in general since there are only 2 lines, you still have to transfer to a bus in the end.
The station building has an open top area, accessed by a long string of escalators or via the lift to F15 in the Isetan department store. Outside, you go up yet again to get to a 360 degree viewing platform, although the glass is pretty thick and colored. Strangely, at that height you are not far from the top of the Kyoto Tower, which is just opposite the station.