Surprise rules, does a character even have a reaction to take before the start of their first turn? I

Jump to another target: what happens when someone rolls a Critical Hit on Chaos Bolt?

The right most picture of Diagram 2.5: Cones Using Tokens in XGtE violates how cone effects are described on PH 204

Can Mobile Flourish be used during your turn?

Are there rules for dashing multiple turns in a row?