Step 1: Find Vinteum Ore
Step 2: Make vinteum bars
Smelt the vinteum ore in a furnace or blast furnace to get vinteum dust.
Combine that with iron to make vinteum coated iron.
Then smelt that to make a vinteum bar. You will need 5-10 of these so make extra.
Step 3: Find a Spellmonger Villager
New buildings spawn in villages with spellmonger villagers in them.
Trade 5-10 vinteum bars to get the Codex Arcana. Read the book and it will guide you from there!
There will be methods to start the mod in the future that don't require exploration or a village.