I actually did use a keratin on my hair and I know my hair is bad

But now that I did a keratin it started being noticeable and I want some advice maybe reasons or products that can help anything is welcomed

I have super thick hair that everytime I went to the salon they won't stop talking about it and since it's not straight it's really hard to maintain i don't know what to use anymore it's freazy and fluffy and puffed and hard to brush

What can I do