Direct hair dye questions

So I’ve always wanted to dye my hair, but I’m a natural redhead (darker kind, not ginger kind). So my parents have always been pretty adamant about me NOT dying my hair.

I like my hair color, I’m not upset with it at all. But I also want to explore other colors.

I heard direct dye doesn’t harm your hair, and you don’t have to bleach. I understand I won’t get to try pastels or greens (due to my hair being darker), which is fine. I’m more into blues and purples.

So is this true? Will the dye fade, and will I be left with my natural hair color when it does fade? Will it cause any sort of damage?

If the answers to the questions above are positive, let me know brands you recommend, thanks!