How To Treat Dandruff And Itchiness Of Scalp?

HELLO MY NAME IS SHARDA WHITFIELD AND I HAVE A SERIOUS PROBLEM WITH DANDRUFF. MY SCALP IS WHITE ALL THE TIME IT ITCHES BLEEDS, I HAVE BIG GIANT FLAKES I CAN WASH MY HAIR TODAY AND I HAVE TO WASH IT AGAIN THE NEXT DAY. MY DANDRUFF IS REALLY REALLY BAD AND IT ITCHES SO BAD AND I WANT IT GONE. WHAT DO I NEED TO DO PLEASE HELP ME