@Pasta-san Ok i will explain why people have the idea that determinism is the opposite of free will.
Determinism is the theory that the source of an event, including your choices, are determined (hence the name) by a previously existing cause.
The things making the decision come from your circumstances, it is cause and effect, you are not the one making the choices, is the environment, your upbringing, your experiences, the weather, the policy of the place you are in, the people you have interacted with, the state of your health, the dog poop you step on early that day. Is not you, is the things that happen to you, your past determines your future.
That's what determinism is about, is about figuring out the why someone took a decision, a deterministic explanation runs opposite to the idea of free will because the reasoning follows things that the person can't control, and that instead control the person.
Determinism is not only applied to choices that have already been made, it opens the possibility to make predictions, if you have a complete picture of all the causes that may lead to the outcome of a certain event, then you can determine what the outcome will be.
Thus if you have all the factors that explain how someone behaves, you can predict how that person will act in the future.
It has nothing to do with making the same choice every time, or making a different choice each time, it is about pointing out why you made the choices you made, and what choices you will make.
Why did you made the same choice 15 times in a row? Because x, y, and z factors, because you had that education, you eat that food, you encountered that person, you were of that demographic, etc.
Why did you made a different choice all 15 times? Because x, y, and z factors, because you had that religion, your back hurt, it was raining, you were of that era, etc.
Why will you make those 15 choices in the future whatever they may be? Because x, y, and z factors, because you had that age, your dog died, it was Friday, you are from that city, etc.
It is a model to explain things, you find the cause behind that led to the choice, it seeks to map a chain reaction by revising all the spheres that influence a person to make a choice.
Why did you thought things through? Because x, y, and z factors led to you thinking things through.
Why did you stuck to your guns? Because x, y, and z factors led to you sticking to your guns.
Under determinism, an intention is just a result, a effect and not a cause, people don't behave randomly their actions are the result of a series of causes, and free will is an illusion.