i want to make a bounty datapack, but dont really know how to code at all. i need help.

i wanna make a bounty datapack where first couple of kills your bounty is just iron [goes up by 10 3x] bread [25, 30, 35] coal [30, 40, 50]. but after 3 kills, your bounty gets better rewards, golden carrots [25,30,35] emeralds [10,15,25] and lapis [45,50,55] and then after you get 6 kills you get the max amount of rewards, that go up for every kill, so diamonds [2,4,6,8, going on] netherite scrap [1,2,3 going on] and golden apples[3,6,9 and going on. i have almost no experience, and just need help. so if anyone wants to help i would appreciate it a lot.