You can get a good exposure of the moon at f/11 with the shutter speed set to the inverse of the ISO. At ISO 100 ... that's 1/100th sec. At ISO 200 ... that's 1/200th sec, etc.
To "fill the frame" with the moon using a camera that has any APS-C size sensor (like your Canon T6), a focal length of around 1500mm would be a tight fit. Around 1100-1200mm you get a "comfortable" fit.
To make it better... you've got a couple of options.
First, when you think about photographic lighting, the saying is "you can't have good light without good shadows". Moving the light off to the side allows the subject to cast shadows and that creates visual cues as to the 3-dimensional texture of the surface.
When the moon is "full" in means the Sun is basically "behind you" (it's like using on-camera flash). If you shoot the moon when it isn't full (say 1st quarter phase) then the sun is lighting the moon from the side and you get loads of surface details created by all the shadows on lunar mountains and craters. When I shoot the moon by itself, this is usually what I go for.
Another technique that will be helpful (especially at a 500mm focal length) is not to shoot at night.
So imagine your same photo... but imagine adding in a landscape in the foreground with the moon that large. It could be mountains, a city scene in the evening, etc.
On the day "of" the full moon, the moon is rising AS the sun is setting. By the time the moon is high enough to shoot, the sky will be completely black. But the moon rising roughly an hour later each day (it's probably closer to 55 minutes later, but in rough round numbers you can go with the hour estimate).
Knowing this ... if you want a more interesting moon that isn't all by itself, shoot the full moon the day "before" it is full. On that day the moon rises about an hour before the sun sets. By the time the moon is high enough to get a good shot, the sun will probably have set BUT... the sky will remain dusky blue for a while.
That means you can find some attractive landscape and shoot the moon in that landscape scene. This could be moonrise over a city, over a prairie, over mountains, etc. but it gives you a chance to get some rich detail into a photo that still features the moon.
The tricky bit is figuring out "where to stand" (much of photography is about "knowing where to stand" to get the shot) so that the moon is exactly where you want it relative to the rest of the scene. To do that, there are loads of apps.
You can use:
etc.
All of these apps tie in astronomy data regarding the path of things like the Sun, Moon, etc. combined with map data to help you work out exactly where you would need to be to get a celestial body exactly where you want it.
Since, often times, you only get a limited window of time to get these types of shots (where the sun or moon must be in *exactly* the right spot) and go out a day or two ahead of the day you *really* plan to shoot and practice to make sure you're getting the app to work correctly and it's giving you good predictions, etc. If you miss the shot ... you might have to wait a month to try again (and hope that it isn't cloudy.)
Good luck!
