I do not think I have ever seriously used kable but as I understand it Yihui intended it to be really basic so I doubt that it will handle what you want.
seriously.
When you say, "i know how rotate a whole row or a whole column" are you doing this is with the Kable (knitr::kable() function or using the kableExtra package?
I see that one can rotate a row or column with kableExtra but I don't see how to do a single cell. You may be stuck with the latex code.
I believe that the flextable package may be able to do what you want though it may not be flexible enough.
library(flextable)
ft_1 <- flextable(head(iris))
ft_1 <- rotate(ft_1, i = 1:2, j = 1, align = "bottom", rotation = "tbrl", part = "body")
ft_1