The word Bo is a combination of the letters beis and aleph, rightly so. You need the beis, which has three sides, symbolic of the three partners in creation to create an aleph, (and thus the open sided, birthing beis vis-avia the aleph) one new individual. G-d was telling Moshe that He was also his Av which is Bo backwards.
Including the vav for the gematria would equal nine, equivalent to the tesha yemei ledah to create an individual.
We know the Torah begins with a beis, and the question is why. It may be suggested that G-d is the ultimate symbol of the aleph, as He is omnipotent, and G-d didn’t want to begin the Torah with any letter promoting His essence, as G-d seeks humility.