It seems that you grew up in a negative environment. As a grew up my i never experienced to be scared on failing my grades because my parents did not set a very high expectation. They just let me study and supported me weather i get a high or low grade. They do not demand and pressure me to study very hard and get this grades. This is just a suggestion do not do to your children what you had experienced when you are growing up. Being in that kind of situation it can affect their mental health and the fear deep inside them will grow and it will stays in their heart and mind forever. For you to be able to make a lot of money you have to find other means like finding a side job, creating your own business etc. If you will pursue your target goals then you will be able to earn a lot of money. Just be patient and work hard.
The way he was raised was way too negative for a kid to be raised and what he is going through is evidence for what he has been through in his childhood. According to him, it was his mother who has been so harsh on him which is another thing one cannot believe because generally it's fathers who are harsh on their children so that they learn the things the hard way and have a better future but this is something different.
Those parents who are harsh on their children on another level need to understand that this thing will have a negative impact on their minds in the future and they will be very vulnerable to even the small things and this negativity will never get out of their head just like what's happening with OP.