Sending Spell and Trap Cards on your side of the field to the Graveyard is a cost for activating this card.
You can activate a Normal Spell Card, such as “Raigeki”, then chain “Emergency Provisions” and send “Raigeki” to the Graveyard to gain 1000 Life Points, and the effect of “Raigeki” will still resolve.
If your opponent activates “Heavy Storm” you can chain “Emergency Provisions” to send your Spell and Trap Cards to Graveyard first (and gain the appropriate amount of Life Points).
You gain the Life Points from this card’s effect in one lump sum, so if you control “Fire Princess” her effect will only inflict 500 points of damage.
The effect of this card does not “destroy” your Spell and Trap Cards; it “sends them to the Graveyard.” So, for example, you may send a Spell Card to the Graveyard with a counter on it from “Magic Reflector”. You can also send “Fusion Sword Murasame Blade” even though it cannot be “destroyed”.
If you control a monster equipped with “Premature Burial” and you send “Premature Burial” to the Graveyard to activate “Emergency Provisions” the equipped monster is not destroyed, because “Premature Burial” was not destroyed. The same is true for Toon Monsters: if you send “Toon World” to the Graveyard with “Emergency Provisions”, Toon Monsters you control are not destroyed.
If you send “Smoke Grenade of the Thief” or “Blast with Chain” to the Graveyard for the cost of “Emergency Provisions” their effects do not activate, because they were not destroyed.
If you send “Black Pendant” to the Graveyard for the cost of “Emergency Provisions” its effect does activate.
While “Banisher of the Light” is face-up on the field, you cannot activate “Emergency Provisions” since it is impossible to send cards to the Graveyard.
If you have “Imperial Order” active on your side of the field, you may send it to the Graveyard as part of the cost to activate “Emergency Provisions” and “Emergency Provisions” will not be negated.