How precise do you want? The level indicator in the Mixer has no digital readout. Is that what you are looking for?
If so, then download and install the free version of the YouLean Loudness Meter 2, install it and add it to the VST path.
In MEP, open the Mixer, click on FX at the top of the Master track, the + at the bottom, and add it. Play back the timeline and you'll see the readouts in LU's and LUFS, and much, much more.
See also this thread about it. Scroll up as the link points to the last message.
If you prefer more traditional old style analogue and digital meters but still have accurate metering there is a range of meters available free from an audio designer engineer here where ha basically designed them for his own studio use. I would advise reading his instructions first even if you are used to the styles of meter on offer.
I am used to LRMS type meters and find them useful and accurate. While the meters are not plug-ins and can not be used on individual channels within MEP I have found them very accurate at measuring the actual output level of the program. They are also adjustable in their scale of readings.
Youlean Loudness Meter follows the EBU R128 standard for broadcast, the advantage over standard VU meters is if you set 2 audio clips, irrespective of their actual loudness differences, to the same level they will be the same perceived loudness, whereas with the VU meter measuring method there is still a difference in the perceived loudness.
You do have to get used to the different units, increasing an audio signal by 1 LUF is the same as amplifying by 1dB, and -23 LUFs - the EBU R128 level required for broadcast.