Truck-kun - honk honk

No, for a couple of reasons.
(I'm going to assume this was based on the "many worlds" interpretation of quantum mechanics.)
Quantum mechanics has been pretty well-backed-up with experiments that match what the math predicted.
There are many interpretations of quantum mechanics means, and they're essentially unprovable, untestable.
I've heard somewhere that different interpretations can give useful perspectives for analyzing different types of problems.
But they shouldn't be taken too seriously.
Second, from what I recall of the many worlds theory, you wouldn't "go to another world", rather, there would be a "fork in the road" creating a new universe at every moment.
Bob from universe A is crossing the street, in universe A1 he notices the truck and avoids it in time, in universe A2 he doesn't.
In universe A2-1, he manages to survive the collision, in universe A2-2, he doesn't.
A1-1, A1-2, A2-1, have living Bobs.
A2-2 has a dead Bob.