No, the Canon EOS 600D records at a maximum resolution of Full HD (1920 x 1080) at up to 30 fps.
No, the Canon 600D is not weather-sealed or waterproof. It should be protected from rain and high humidity.
The 600D uses the Canon EF-S mount, meaning it is compatible with both EF-S lenses and full-frame EF lenses.
The LP-E8 battery provides approximately 440 shots per charge according to CIPA standards when using the viewfinder.