From my understanding, many worlds interpretation views the actual world (universe) has many branch points. For example, coin flipping may cause two outcomes, but I will experience only on outcome or the other. Which outcome of universe will I go to?
MWI is a minority position amongst interpretations in QM; famously Deutsch is an exponent.
It gives the wave function of a QM ontological weight; with branching occurring at measurement, where typically, in the Copengagen-type interpretations, collapse occurs; I think Everrets original motivation was to remove this 'discontinuity'.
But this can't be quite right; for if no collapse occurs, then the wave simply evolves in time; and branching ought to be synonymous with the wave itself; this renders the notion of branching problematic - after all when one does a measurement, a specific eigenvalue and state is selected from the spectrum of all such that evolve; this suggests that branching is part of the story told to popularise MWI, a kind of myth like Newtons apple.
If then there is no branching, then there are no new worlds for your coin to fall into or choose between.
There is just one world, but quite what what this means is the problematic here, where potentialities are given actual weight, and are rendered visible in the small.
In the Many Worlds Interpretation, you go to both worlds after a branching point. That's why its called a "branch," because the present universe splits into two or more viable outcomes. In one world the coin lands heads up and in the other it lands tails up, but in each you are there to see it if you were there to flip it.
Note that this assumes simple binary, "either/or" branches. In reality there would be uncountably many branching points, most with a handful of possible outcomes each.