The Level meters show the RMS level as a coloured bar and a numeric value at the bottom of the meter and the peak value as a red line and a numeric value at the top of the meter. Levels are in dB below Full Scale.
If the signal generator is playing a sine wave the lower panel shows the
gain and phase of the measurement input relative to the reference input at
the signal generator frequency, this may be useful for checking inter-channel
gain and phase if both channels are fed the same signal.