All of this information (including part #1) is missing a key element: temperature. Temperature should be considered to be an "ingredient" when making sourdough bread. It's not as simple as "do X on day Y, and you'll have sourdough". You may end up with tart/acidic dough...but not proper sourdough.

For a great introduction to making sourdough, I recommend reading the book, Tartine, by Chad Robertson, and browsing Maurizio Leo's amazing sourdough blog: https://www.theperfectloaf.com/