@agriggio’s link covers that. Fortunately, you don’t need RawDigger to examine your raw files.
I wouldn’t do that if I were examining the raw file. And as I and then others have indicated, I wouldn’t process with the base curve most of the time, esp. if you are using filmic.
1. It is entirely possible that your metering is broken. It is not unusual but don’t assume it is so right away.
2. Metering is tied to focusing (and possibly WB). You can separate the two for composing if you prefer a feature like back button focus, etc.
3. Metering is tied to the histogram (or the live view), which is unfortunately the case for all cameras tied to the JPG preview, not the raw file.
4. Due to point 3, your metering would be off say about 1-1.5 EV if your goal is to do ETTR. We call that headroom. For less technical photographers, the headroom actually protects them from overexposure; it is a good thing unless you know what you are doing.
5. Use Manual mode. That way, you get full control over your settings. The are many settings to turn off if you want your live preview to reflect the raw output as much as possible.
6. I had other things to say but I forget…