This is one of the area’s where MSFS is very weak. Unfortunately because they chose to base this on the old FSX methods it’s so un friendly to use it often needs a lot of investigation to track down the var or event required. There is no one place that lists them all out like Xplane has. There are multiple places to start your search but ultimately you will be having to dig into files to find what you want. It shouldn’t be this way but it is. Even then a lot of them are not accessible right now. There is a big votable topic in these forums asking for access to all these currently in-accessible ones. If something moves in the cockpit but doesn’t do much else there will be a var for it but almost every time the var will be one of the ones we can’t currently get at.