ランとシャオ

"Firebending N" is a keyword that represents the ability "Whenever this creature attacks, add N {R}. Until end of combat, you don't lose this mana as steps end."

Any other mana you add during combat will still be lost as normal when moving between steps of combat.

Except for the legendary supertype, the token copies only what is printed on Ran and Shaw unless Ran and Shaw are being modified by another copy effect. It doesn't copy whether Ran and Shaw are tapped or untapped, whether they have any counters on them or Auras or Equipment attached to them, or any non-copy effects that have changed their power, toughness, types, color, or so on.

Firebending abilities aren't mana abilities. They use the stack and can be responded to.

Mana from firebending abilities isn't lost until you leave combat and go to your second main phase. It can be used at any time during combat, even after combat damage has been dealt.

Multiple instances of firebending on the same creature trigger separately, each granting you the appropriate amount of mana.