Does a fighter with improved/superior critical auto-hit on natural 19/18+ or still only with nat 20?

Exhaustion chart alludes to effects that remove levels of exhaustion. Is there a handy list?

Sword of Sharpness, does object include creatures for the effect?

Can I select Shield Master feat and gain shield proficiency?

Does the Draconic Bloodline bonus language also apply to those with draconic origins like Dragonborn, or is it strictly for speaking with full-blooded dragons?

In D&D, does Distant Spell work on a spell that has a range of self?

Does Stealth or Invisibility work within Blindsight range?