Roguelike Adventures and Dungeons is built to encourage adventuring and progress, with an emphasis on randomization and a scale of difficulty.
Establish a Base
You can use the starter blueprint in your inventory to put down a base at the start. This will give you starting supplies, a bed, and you can always steal from your own base if you don’t plan to stay at that location long term.
Sample food, start farming
As you adventure, you will find various edibles via Pam’s Harvestcraft, Cyclic, and countless other mods. If you hover over an item and it notes you have not tried it before, take a bite. Every time you bite a food, you get a chance at a max heart +1. Pam’s harvestcraft requires you to farm to get the greater food types, and the investment is rewarding due to max heart bonuses.
To assist with farming, Make a Water Sprinkler from @Extra Utilities, this is simple to make and will let you accellerate crafting any ingredient.
Get a cow farm, make a backpack
Inventory is immediately going to be an issue for you, and @Improved Backpacks is there to help along the way. One of the more annoying resources to craft backpacks is the amount of leather, so getting a steady supply is needed. String can be obtained from deconstructing wool or from the abundance of spider webs in various dungeons.