Tips to get better at hunting on PC

Hello ! I just started playing a few days ago. I play on PC with the keyboard and mouse. Whenever I hunt I only ever get 1star animals. I've been playing with my brothers, and they complain that if they point me to a 3 star animal, once I kill it it turns to a 1star. I'm still clumsy with the controls so I do tend to shot quite a few times before they die. I am getting better, and managed to one shot a few. From my understanding, being able to one shot the animal helps with the quality, but it still never goes up in quality. Is there maybe a better gun I should try to buy? Or amunition you would recommend? My brothers' tip is to stop playing on my keyboard and get myself an xbox controller. Which is not a priority, I feel like there has to be something in game I can do. Thank you so much for your help !!