pot and soil - there are so many options for a medium and so many ways to make each work just fine. Where you live may even restrict what you have access to. Pots.. are pots. I saw no different in fabric vs standard nursery pots. I certainly won't overpay for the cool looking spikey-pots, lol, but each to their own.
I prefer to keep it simple and sow directly into medium. I'm happy to wait for a sprout and don't need to see it germinate. Each method has little nuances to learn to be most effective that are easily learned and in no way an obstacle.
People start plants inside all the time. You'll have to adapt them to the sun before they can handle it all day.
yes, tap water is fine. If your water is very hard, 500+ ppm, it may hinder how you fertilize. ph-balancing should be done regardless of what you use. Heck, i've used softened water without any issues, lol. Just don't do that for a 'mother' sitting in the same pot for years.
as much water as required to fully saturate the pot. If you go soilless, also get 10% runoff. When you re-irrigate is a matter of reacting to an observation -- is it dry enough? There is some variance as to exactly when, but if you repeat at same loss of weight, it'll require the same volume of water, roughly. You learn it in hindsight. you don't choose either of these things out of the ether. You observe and react.
Fully saturating should never cause a problem. That is indicative of watering too frequently or a poorly constituted medium. Partial watering trains superficial roots. don't do that.