How can I tell my parents that I want help, 15 yo

I have been feeling early symptoms of depression for a while now and as they became more and more noticeable i started looking up sympyoms, causes, etc. I am showing most of the regular symptoms except problems with sleep, suicidal thoughts ( I regulary think about how the world would be if i died but I dont want to kill myself ) and physical problems like headaches. I want to get professional help but I fear I cant ask my parents, im sure that they would be supportive but i always struggled with telling my paremts, and other people, stuff going on in my life. I feel like i wont be able to tell them, what should I do?