No Yeast! Easy Sourdough Bread

Due to lockdowns, It's pretty hard to find yeast at the supermarkets.
So here's a super easy to follow tutorial on how to make bread at home, no yeast, no baking soda or baking powder.
Enjoy!

INGREDIENTS YOU'LL NEED
LEVAIN
50g Mature Sourdough Starter (~1/4 Cup)
40g Whole Wheat Flour (~1/3 Cup)
40g White Flour (bread flour or all-purpose) (~1/3 Cup)
80g Room Temperature Water (~1/3 Cup)
REMAINING DOUGH
900g Unbleached Bread Flour (~7.5 Cups)
100g Whole Wheat Flour (~0.8 Cups)
750g Room Temperature Water (700g initially + 50g added after autolyse) (~3 1/8 Cups Total)
20g Kosher Salt (~3 1/3 tsp) (VOLUME CAN VARY DEPENDING ON TYPE OF SALT USED)