It is permissible for a man to tie his hair and to dye it.

A man is allowed to tie his hair, and a woman ties her hair; what is forbidden is imitation.

Allah does not allow a man to imitate a woman, nor a woman to imitate a man. The Prophet ﷺ cursed men who imitate women, and cursed effeminate men, those who imitate women.

But if a person grows his hair long without imitation or dyes it, there is nothing wrong with that, if Allah wills, the Exalted.