Hair product recommendations please

My niece has type 3b hair and I would like to get her hair products. the other day while she was at my house, she was telling me that my daughters hair style was really cute. I was all excited and asked her if she wanted me to do her hair like that. But told me that her hair is ugly and frizzy so she can’t have her hair done like that. so my instant response was

“Your hair is beautiful, who told you that?” Apparently another little girl in her class has been making fun of her. I’m hoping that getting her some product for her curls and teaching her how to use them will give her a confidence boost. The only problem is that there are so many different product lines I’m confused what to get her for her age which is 7. ~~ edit~~ we had this conversation while I did her hair up into the cute buns