Changing others is nuts, better find a way to change yourself.
Capricorn in life by definition is supposed to show a more high-cold, you are high-cold Capricorn forced into a nagging old mother, gradually you are in life is how to let a person is not save.
No matter what your mom's constellation is, the world is a family of pro-moms, when the mom's are like this, you'd better find a way to make a change.
Study well, every day, show a understanding of you, mom naturally nagging will be less. The same sky with the same mom, who's mom is this way, nagging is a kind of normal, first you have to learn to get used to it.
If you really can't get used to it, you can raise the issue with your mom, but of course the odds are that your mom won't change. You need to show yourself to be more understanding, so that there is nothing wrong with your studies and the way you deal with people, so that your mom has no points to nag, so that you can naturally withstand less nagging.
When you become good enough, your voice in the family will increase, and your mom won't be able to focus on you all day.
Cultivate some hobbies for your mom and let her go about her business. When you are truly independent, when you are able to take control of your own life, help your mom to develop some new hobbies, even if it is a square dance, sing a song or something, it is better than staring at you every day.
You need to put your mom at ease so she can have fun. This in itself is a very reasonable closed loop, you need to do to make yourself good first, your mom can rest assured to go to their own lives, you can listen to less nagging.
It's actually a way to have the best of both worlds, to make your mom's life happy and to make your own life happier.
This approach doesn't just apply to you, it can apply to every child under the sun as well. If you really think that what your mom said is wrong, that it doesn't make any sense, then you make the right show, make something that really makes sense, so that your mom can see what you are capable of and how good you are.
Whether you can listen to less nagging depends on whether you try hard enough.