What type of tree is this?
It is a mulberry.  What isn't clear from the photos, and may not be clear without a DNA analysis, is whether it's a hybrid of the native red mulberry and the white mulberry imported from Asia in the hopes of starting a silk trade in North America (white mulberry is the main food source for silk caterpillars), or whether it's distinctly a red or white.  The berries won't always indicate this, and the leaves won't always indicate this.  At this point, our red mulberry has seen sufficient habitat loss that most new mulberry trees are hybrids.