Gaining Motivation Despite Strict Parents

I'm gonna be honest, that sounds like emotional abuse to me. Maybe it's not, and it's hard to judge a situation from a single example, but the way you wrote this post makes it sound like this is a regular thing. Definitely talk with them, since a lot of parents aren't aware that this behavior is harmful. On a side note, if you struggle to focus on something you can try a mini reward system. Get a few of your favorite treats (candy, chips, etc.) and spend 10-15 mins focusing on your task. When you're done, get one of the treats.

Have you tried talking to them honestly about the situation? Explain to them that in the way they behave they are only making it difficult for you, I know the problem, my parents were also very harsh with me, unfortunately, the only thing that helped me, in the end, was moving and living alone, that's how I developed full independence since my parents weren't always there for me.