Duvet ring pink

Should I do the Brazilian Keratin Treatment? - brazilian keratin before and after

He sent me last week about my hair set in a relaxed and according to the answers I got here and some other places, we decided against it. Now I am in the Brazilian Keratin treatment. My questions are:
He came to her straight hair?
How long before I ever do?
Does it work better if the color of the hair first?
How?
Thank you!