Is the upright bass hard to play?
Playing the upright is difficult. It's a physically demanding instrument that takes a long time to work your body, arms, and fingers into being able to play efficiently enough to avoid injuries.
What are the notes on an upright bass?
You can think of it as a giant violin; the construction is very similar. The upright bass is tuned in fourths: E, A, D, G, like the lowest four strings of a guitar, but an octave lower (this makes it the odd man out in the orchestra string section, where the other instruments are tuned in fifths).