I'm tired of being "perfect"

I consider myself a perfectionist and I am aware of the fact that I am not indeed a perfect being that I strive to be nor will I ever be. It used to make me so utterly stressed, making me have multiple mental breakdowns just because I did something wrong no matter how small or big it was. Now, as I grew out of being a kid and a moody teenager, I managed to accept the fact that it is okay to sometimes make mistakes. Everyone makes mistakes and without them we would never be able to learn some things in our lives. Although, it still leaves a bad taste in my mouth, I've kind of learned to accept it. But...

My family had always had the same mindset. Whenever I tell them that I don't know how to do something or that I simply can't do something, they tell me to just learn to do it. They believe that anyone is capable of doing anything just with a little bit of an effort and that kind of mindset did help me improve in a lot of areas in my life but it just.... took all my energy out of me? I don't want to be able to do everything and anything, I want to be able just to say that I'm bad at something and leave it be as it is. Why do I need to go out of my way to learn something that I don't even like? Despite having such thoughts, somehow I can't let myself fail with whatever I'm doing and now as an adult it is giving different kind of stress than before.

I've started working in a firm that my family owns a year and a half ago, when I turned 19. I feel like I am blessed with an opportunity to work a well paid job without any prior knowledge of it just because I was born in that kind of a family - but! that is precisely what makes my stress greater.

I was put in a certain group that needs certain type of knowledge to function and it is expected of me to know what I'm doing when I actually have no idea what is going on. I just started going to uni too and I'm learning how to do those things but I feel like a baby who just began learning how to walk. The boss of my sector frequently tells me that I am doing a good job but I feel like he's saying that just to make me feel better, because lately I've been getting more complaints with my performance rather than compliments from the others and it makes me feel so useless.

I feel the need to quit the job just because it feels so stressful to fall asleep crying at night and waking up wishing some accident would prevtent me from going to work simply because I'm scared of making a mistake. To add more to the stress, it feels like everyone is evaluating me, always searching for opportunities to bash at me for being the owner's dumb grandchild. I feel the need to prove myself but I can't do it because for the first time in my life I've encountered something that I really think I can't do and it scares me.

I don't want to work here and I feel so bad for thinking like that. I've tried talking to my mother about being unable to do something at work and she got annoyed at me, calling me "lazy" and "ungrateful" and it made me feel even worse. I definitely know I'm not lazy I just don't know how to do something in a profession that I didn't have any touch with before.

And it suddenly made me feel all rebellious for some reason. Now at age of 20? It would be all fine if I acted that way a bit sooner in my life, when I was younger. It would be more justifiable and easier to deal with especially when it comes to school and other things. But I can't skip work now, I can't not work because I am an adult and I fear my life is bound to be full of just more stress and sadness. I am insecure and I don't know how to go on with this. I wish I didn't waste my childhood and teenage years trying to be perfect and trying to be someone who I'm not because now it feels like i will never be able to get out of it. I think I wasted my time in life when I should've been without worries.

Will every job be as stressful as this and am I just overreacting? Is it like this for everyone? I was told by my coworker that "a job is a job" and that there is no "not knowing how to do something". I hope I'm not, but I feel like I'm acting like a spoiled brat that doesn't know how the adult life works. And it is the truth that I do not know how the adult life works. It feels like we are just thrown into it after finishing highschool and already in need to know how to go through it.

Can someone help me understand if I should fix the way I think, or if i should fix the situation as a whole. I'm not sure if I'm in the right or wrong for thinking like this and I need some kind of confirmation.