You just downloaded the modpack and created a world five minutes ago. Using your Minecraft knowledge, you decide to start punching down a tree to get wood. Not only does it take a lot of time to cut it down, it also doesn't drop anything. On this page, you will learn exactly how to get started, as it can get a little tricky. You can also watch Shivaxi's Guide, a beginner's guide made by the creator of the modpack.
First Step: Flint
What you want to do first is to find yourself some gravel. Gravel is commonly found near water sources or underwater. Dig it up over and over, until you get flint. You will want to take that flint to a "hard" block (stone, bricks, etc.) and right-click on the top surface of said block to break it into flint shards. You will then want to break down leaves until you pick up a stick. You will need to take one flint shard and put it on top of a stick in your crafting grid, to get a flint knife.
Are you having trouble picking up your gravel, flint shards, or sticks? Not to worry, this guide has you covered. RLCraft includes a mod where item pickup functions differently. To pick up an item off the ground, you can either right-click on it or crouch with Shift nearby it to pick it up. Crouching will pick up all nearby items, whereas right-clicking will pick up only the item you're looking to grab. It's fairly useful; you can use this mechanic to pick up items through small holes and stuff that would usually be out of reach. And now that you can pick the items up, you can continue with the tutorial. If you can't find any gravel, however, you should try dying until you do. Each time you die you respawn somewhere new.
Plant Fiber and Plant String
You will now want to use that Flint Knife to break down some grass. This will give you Plant Fiber, which you can use three of to craft a Plant String. Plant String is crucial, as you can craft wool out of it, but especially because it is what you will be using to create your very first axe: A Flint Hatchet.
The Flint Hatchet will be what you will use to break down your first trees, in order to get wood. Since this modpack includes the Dynamic Trees mod, chopping down a tree is fairly easy, as you only have to break the bottom block of the tree for it to fall entirely. You still need to be careful, as the tree will fall and crush you if you are standing underneath it as it falls. Trees normally fall towards the opposite side of where you're cutting it from. If you sneak while doing so, it falls towards you instead.
Obtaining Wood Planks
As you might quickly notice, placing wood logs in your crafting grid does not give you four wood planks (With the exception of fir wood). Instead, you have to place that log on the ground and right-click its top surface with your hatchet (or axe) to get some wood planks out of it. Doing the same with wood planks yields sticks. Once you get further into the game, you will be able to craft a saw, which can be used to obtain either four planks or eight sticks out of a log, or two sticks out of a plank, which is significantly more efficient than using a hatchet.
Getting Better Tools
Once you managed to get enough wood planks, you might want to make a Wooden Pickaxe, to be able to go and mine some stone. However, you might notice that mining Stone does not yield Cobblestone, instead you end up with your inventory filling with Rocks. To get some cobblestone, simply put four of them in your crafting grid in the same shape that you would use for a crafting table, which will give you one Cobblestone. You will be getting up to five different types of rocks: Rocks, Andesite Rocks, Granite Rocks, Diorite Rocks and Sandstone Rocks. All of them, except for the latter, will yield their very own type of Cobblestone upon being crafted, but every type of Cobblestone can be used anywhere you would normally need to use regular Cobblestone in a crafting recipe, such as Stone tools.
When you first try to make a torch, it will be unlit. You can light these torches by making a Matchbox, with 3 paper and 3 wooden slabs, and then putting an Unlit Torch with the Matchbox into the crafting area! You can also use a Flint and Steel, which can be crafted with 1 flint and 1 iron ingot, to light torches the same way.
Some players choose to skip wooden tools completely, which can be easily accomplished by collecting rocks off of the ground, crafting them into cobblestone and making stone tools. This method, while it helps craft better items faster, can be quite slow if you are in an environment with very few rocks on the ground.
Crafting a Bed
In order to set your respawn location, you need to craft a bed. Just gather up some extra wooden planks and craft wool from plant string and you'll be ready! Be wary, though, since clicking to sleep has a 1% chance of spawning a Reaper, a flying mob who shoots dark orbs at the player, giving the Blindness and Fear debuffs. You can also look for a naturally generated structure to serve as your shelter, as they can occasionally have tools in their chests!
After you set your spawn, you are free to die as much as you wish without losing your home. However, while this drastically lowers the risks of exploration, you may find it tough to defend yourself against the unfathomable amount of creatures after your head. One of the best ways of defending yourself is to craft a shield. There are multiple kinds of shields, but the cheapest one can be created with 6 planks and a stick. Place the stick in the center of your crafting grid and surround it with planks, while leaving any two opposite corners of the grid empty. This will craft a Crude Shield, which can be equipped by holding it in your hand and pressing F. You can also upgrade your shield by putting it in the center of your grid and putting the desired material on the four surrounding spaces. Using stone is your best choice at the moment, as other materials cannot be used until you upgrade your defense skill via the skills menu, which can be opened by bringing up your inventory and selecting the appropriate tab on the left. More information on skills can be found here.