So the Milky Way has an estimate 100 billion stars and there's an estimate 100 billion galaxies. The Ingredients that make up life as we know it are abundant in the universe.

The statement that there's an estimate of 100 billion galaxies is misleading because cosmologists have absolutely no idea how many galaxies there are in the universe. There's not even an estimate.

*Any* estimate is not only misleading but also 100% inaccurate. It's quite possible, even likely, that there are an infinite number of galaxies in the universe. If its not infinite then its finite. Given that fact ask yourself what the difference is between an infinite number of galaxies and a finite number of galaxies. What do you get?

If there is an infinite number of galaxies in the universe then the probability that there's life elsewhere in the universe is 1. A probability of 1 means that its exactly 100% certain. If that's true then it follows from that that there's an infinite number of worlds which have intelligent life on them.

What determines all of this is the mass density and nature of matter in the universe. To be 100% precise it depends on the stress-energy-momentum tensor and the cosmological constant. That will determine the spatial geometry of the universe. If you're not familiar with the cosmological principle then it's stated as follows. From Wikipedia:

https://en.wikipedia.org/wiki/Cosmological_principleIn modern physical cosmology, the cosmological principle is the notion that the distribution of matter in the universe is homogeneous and isotropic when viewed on a large enough scale, since the forces are expected to act uniformly throughout the universe, and should, therefore, produce no observable irregularities in the large scale structuring over the course of evolution of the matter field that was initially laid down by the Big Bang.

This implies that the number of galaxies per unit volume is a constant when that volume is viewed on a large enough scale. Under these conditions there are three possibilities for the spatial geometry of the universe.

1) Closed and spherical

2) Open and flat

3) Open and hyperbolic

If the universe is open, which it appears to be, then the universe is infinite in size and contains an infinite number of galaxies.