these programs help you increase your dexterity with the mouse, and are helpful also besides gaming, on any computer task; the mouse is a tool, you have to exercise it and it will get better.
in SC particularly, to increase your aim, you might also want to improve your movement. moving the ship, to help you aiming, knowing that your movement is going to change your projectiles vector, and learning how different ships move and defend themselves, by flying them also improves your skills there. if you start to “know your ship”, you will notice big improvements fast.
basic aiming on the screen alone might give you the edge in a dogfight, but ultimately you can compensate less aiming skills with team work. use weapons where you already hit a bit, and improve them. dont go for weapons, which need a lot of aiming and timing at the same time like a shrapnel, first; if you have a hard time, use it early, when you are concentrated, and later, when you are warmed up, but always only if you have positive morale.
some people are better this early. you seem to be younger, so the good news is, you still have the potential to acquire these skills. don’t measure yourself too much with your dad, instead, work together and try to teach each other, that is the strength of community. watch each other play. you will discover that there are many other skills involved, than aiming, and you can master all of them.
it helps to delibaretly use a ship once in a while (you got 3 slots anyway from the start, and get a fourth at rank 12) where you are still struggling, and on the other hand, use another, where you feel already safe.
i am often first on the leaderboard with only 2 kills myself; it is somewhat of a standard pvp thing, since i usually play a lot of support ships to help the team win. who cares about the numbers, if you feel you worked for a victory and won? good luck.