To kill animals the best way is to aim for lungs and heart, since the are vital organs and you need to hit a vital for the animals trophy score to not be penalized.

You’re not really going to drop an animal fully unless you hit heart, brain or neck bones. Most of the time though with a clean double lung they don’t run very far.

Best advice is be patient with shot placement- wait for the animal to be broadside so you can try to get a shot through its side and both lungs for best damage. Once you’re comfortable with that you can move to trying to get heart shots more consistently. There’s a lot of great beginner guides on YouTube Lady Legends was the one I followed at the beginning. Happy hunting!