I’m pretty much confused with my inventory and where to find certain blocks. To clear up my inventory I deleted my slingshot and I actually wonder how to get it back.
The only way to get it back is if you choose to respawn (either from your home or the capital). You will lose your whole inventory, but will respawn with all of your default blocks/equipment.
To respawn, once you’re in-game, hit ESC and choose one of the respawn options from the menu.
As for finding certain blocks–the ‘P’ key is your friend, as is building a block bank somewhere on your chosen primary world. There’s plenty of lovely stuff out there to find and mine–with infinite mode on you can do a ‘remove and replace’ wherever you are and then carry it home (not by respawning!) and put it in your bank. (Which is not a game thing–it’s just a part of your home area where you dump blocks, in case that wasn’t clear.)
Keeping your home area far from the capital discourages predation. 🙂