Dandruff/dry scalp

Hi ladies I don’t know where to post this but I need recommendations/advice on how to get rid of my dandruff. At first I thought it was the Castro oil I was using but I’ve noticed my scalp is just dry looking with build up and It’s gotten so bad my hair is so flaky. Can someone recommend products or pictures of products that help you? I’m so embarrassed going out with my hair having so much flakes :(