"You awaken on a small island in a strange empty void. Near to you is a chest with a message inside. What could this mean?"
To play the skyblock map, use the "Create From Template" option when creating the single-player world.
This modpack is not particularly long or difficult, and is more meant to emphasize flavor, creativity and role-playing immersion. In fact, it's basically just meant to appeal to my personal tastes for playing Minecraft. ;)
This pack assumes you are familiar with modded Minecraft and JEI. It is not designed to teach you how to use any of the mods.
If you're not sure where to get started, try working your way to "Forestry" and "Tinkers Construct" machines.