You can find them in your country's support website for your camera. You didn't mention what country you're in, or what camera you're using, but for LUTs, I don't think it matters.
So if you are in the USA, and your camera is a C70, for example, you can go here:
https://www.usa.canon.com/support/p/eos-c70?tab=drivers_downloads
Look for Downloads, Software and Drivers, and then "Canon lookup table Version 201911".
Probably this will work for any country or camera, but it's worth finding the correct website for your country and camera and bookmarking it, because that's where you'll get things like firmware updates.
As for the LUTs, you'll find a whole load of stuff in there. I recommend:
- 3dlut (1d is obsolete)
- 65grid-3dlut (the others ae fairly obsolete, but if you have an old monitor e.g. which only supports 33 grid, you would use that)
- full-to-full-range (only choice)
- then the colour space conversion you want. For example, if you shot log3, you would use "CinemaGamut_CanonLog3-to-BT709_WideDR_65_FF_Ver.2.0.cube"
That should do it.
