How do I introduce my depression (and so on) to my parents?

Hi, new user here so sorry if this isn't exactly the right place to post this but here we go :

I'm 17, I have a messy life right now and even if I should be studying at the moment, I really can't focus on my homeworks because I feel very demotivated and exhausted, there's too much pressure (especially from my parents, they aren't really helping me out on this point) so it feels very tiring to work..

But it's been going on for 2 months and I can't let this happen any longer, I need help but I have to tell my parents about all of this mess too and explain why I look so lazy and stupid right now and also that it would be nice getting therapy.

I really don't know how to talk about it with them.. I fear that they might not understand my struggles and that we end up having a argument or that I would have a panic attack too or that they wouldn't consider getting me a therapist because it's too "pricey" and move on and do nothing...

How do I tell them all of this? Am I just being too anxious for nothing ?