I made Destiny 2 because I really like this game, and I wanted to make it in Minecraft. This is also a currently horrid WIP, you've been warned!
The first thing you might want to do is to go to the Moon (via director(via home button)) Once you are there, look around for some alloy, it's used to make guns. WARNING, GUNS ARE A HEAVY WIP! The sidearm is being fixed, don't make it. Once you have the alloy ingots, you can make a sniper or a hand cannon.