Hi
I don't know how school works in your country, but in my region many people drop out of school both because the school doesn't work well and because they are born into very ignorant family contexts.
I know very well what imposter syndrome is, I also experience it constantly. Because of this syndrome, for years I have lived my life in total apathy because I considered myself good for nothing and being such I could not aspire to anything good.
I went through really bad times, I lost a lot of weight and I didn't want anything.
I missed so many opportunities, that now I'd catch right away!
I know my words will be useless in this situation, but... always remember that your school grade doesn't define who you are, you are not a grade. Studying shouldn't be a social obligation, but it should be a way to learn new things about the world, to feed our curiosity, to guide us in comparison with each other, to become free!
Because culture makes us free, aware, it makes us human.
And you know what? Very often in school they don't teach you this!
They give you a series of sterile notions to learn, and that's it! (Moreover, in many countries culture is manipulated by the Political power, so people do not grow up as human beings but puppets)
Teaching means planting a seed, it means nourishing not only with knowledge but also with the soul. We are not robots who have to learn the lesson for the next day or how to do the math problem, we are human beings who, in addition to learning these things, need to mature as individuals, we need to understand our identity and acquire the tools to face real life!
Because life out there is ruthless.
My country offers many scholastic paths, I chose the one in which humanities and scientific subjects are equally studied. I've had really bad teachers... except one: my teacher of Italian literature and Latin literature.
And then (since my teachers taught badly) I used to watch History and Philosophy lessons from a very good professor on YouTube.
Thanks to these two people, I've learned to look at the world with different eyes, I've learned to dig into the essence of the human being, and I've learned to understand myself, because that's exactly what the humanities subjects are for.
I understood that I can do it, that what I experience is experienced by millions of other people, that we are all in the same sea, and that if we force ourselves and stop to reflect and help each others, everything will be fine.
Be strong! You are not a grade! You are much more, find out who you are.
And if you discover that you don't like studying, look for an alternative, you're not a failure because you don't want to get a degree, you just have to understand what you want.
You don't need a degree to find a job and there are people without a degree who are much more cultured than those who do! Because they are simply people who learn for the pleasure of learning.
So even if you don't go to College, don't
stop learning, ever.
In human history we have had many people who have been successful despite not having very high grades in school, the first that comes to mind is Einstein 
Obviously we must not become Einstein, but we must have his curiosity! (besides being a scientist, he was also a philosopher, that's why he managed to keep his humanity despite the Nazis forcing him to unheard-of things)
I am not saying that we must all become philosophers, but that we must learn to know ourselves and to believe in ourselves. (I advise you to read Daniel Pennac's book "School Blues" and Salinger's "The catcher in the rye")
What I'm trying to tell you is to study only for yourself and don't worry about the grade, the important thing is that you believe in yourself! If you feel confident in what you have studied, it doesn't matter if the grade is lower than you expected.
You must be PROUD of what you do, you must know what you want, you must BELIEVE in yourself.
You have to believe in yourself, you have to believe it, you have to do it.
Stop letting that damn imposter syndrome win, it will only sink you, some get back up... and some don't!
I got up, today I attend university and work to pay for my studies.
And I decided to go ahead because I like studying, even if... I have low grades.
At first I thought I wasn't able to, then I learned to ask for help.
I've taken a few reps, my grades have improved but I don't take the highs, but I never wanted to!
I am satisfied with myself. I believe in me. I try to improve myself every day, but without pretending to be "the best".
Life is stressful, family often doesn't help, society wants us perfect... but you don't have to care.
Even if it takes longer than others to figure out your way, what does it do?
There are people who don't even have a roof over their heads, so we have to go ahead for them too, in my opinion!
Take your time, don't rush, the solution is ALWAYS found, but you have to believe in yourself.
Yet... We don't always make it alone.
Sometimes being strong isn't enough.
Sometimes we HAVE to ask for help!
There's nothing wrong with doing that. I decided to take some reps, which helped me, but mental health is the FIRST thing.
I'll go to a psychologist as soon as I can, we ALL should go to a psychologist (obviously we have to choose one with whom we feel good).
Unfortunately the economic part is an obstacle for many of us, but you can also confide in friends, don't be afraid! Even if you don't have friends you can trust in real life (like me) there are tons of virtual people like us on this forum with whom you can let off steam.
Never withdraw into yourself, whatever happens, DON'T.
Start loving yourself, please, we are candles made to burn, we must burn this life and make it our own
And take your time to discover yourself as I mentioned, I remember a famous quote that says:"How many roads must a man walk down before you call him a man?"
It doesn't matter how many times we fail, failing is fundamental, because if we don't fall... we won't be able to get back up stronger, right?
I've heard of this w others before but it sounds weird to say I'm honestly afraid to be treated, I don't remember who I was before all my health issues happened so I'm basically having to completely rebuild myself into a better and new person and idk, drastic change is scary.
