"He can't dance."

Translation: 他不会跳舞。

[deactivated user]

Haha same

[KarmaAkabane7757]

他不能跳舞 is not ok?

[MalBrood]

能 is more common in having permission to do something, but in the negative sense you'd use 不可以.

[TMBurn02]

How would you translate "he will not dance" then? Do you just need to add context or a time to imply that 会 should translate to will?