I actually don't use any ennential oil, but the best advice i can give is to find a good shampoo and most of all don't stress your hair
The oils used depends on your hair prorosity which is determines how much moisture and protein your hair can take. If you have low prorosity, use lighter oils like sweet almond oil,argan oil,jojoba 'cos low prorosity absorbs little moisture and protein . And if you have high prorosity hair , use avocado oil , castor oil and so on. You can still use oils like argan oil , jojoba oil, sweet almond oil and almond oil. I hope this helps.
I know lavender oil is great for almost anything it’s honestly my favorite but I really don’t use essential oils for my hair I use argon oil every-once and a while for my curls
I would say none. Most cause irritation/burning to scalp if not used correctly. If you have a specific issue you’d like to address I suggest looking at what a dermatologist would recommend for the specific issue.
Rosehip oil, coconut oil, jobaba oil. You can research some more but this is good and make sure to apply to only the tips! Xx