These possibilities all assume that the Orange Turd wins the 2024 Presidential election. Let's say that his running mate is Peter Griffin of "Family Guy."
1. Trump croaks before he is inaugurated. Griffin will be inaugurated, and will submit a candidate for Vice President to the House and the Senate, both of which must approve by a simple majority.
2. Trump and Griffin both croak before the Electoral College meets. ALL the electors can now vote for WHOMEVER THEY WANT. Woo hoo!
3. Trump and Griffin both croak after the Electoral College meets, but before Inauguration Day. Kevin McCarthy, the Speaker of the House, would be inaugurated. He would submit a VP candidate to Congree as above. The House would elect a new Speaker.
So if anyone were to contemplate canceling the 2024 election by, say, using an RPG to blow Trump's limo sky-high (and God forbid such a terrible terrible terrible thing would happen, and I'm not for a moment suggesting that it would be a good thing, no siree Bob), they would have to also target the VP-elect.
The most fun scenario is when both get taken out before the Electoral College meets. The election would now be in the hands of not the American people, but 535 pretty much random numbnuts. The bribes would flow like the Mississippi in spring flood and the scene in the College would resemble the food fight in "Animal House." Good times!