Color Oops Regular Strength Hair Color Remover, #RS100-1 Ea

My hair is currently a faded purple and i used artic fox dye semiperminant dye. Would this remove the purple?

What is the difference between color opps and color prep?

I’ve been coloring my grey hair with dark brown for years. Should this remove that color? Will it leave the leftover Grey yello?

Will this damage my hair if I want to dye my hair after this treatment?