Part 1) Find the measures of angle BGE
we know that
The inscribed angle measures half of the arc it comprises.
so
angle BGE=(1/2)*[arc EB]
Part 2) Find the angle BDG
we know that
The measure of the external angle is the semi-difference of the arcs that it covers.
so
angle BDG=(1/2)*[arc GEB-arc GB]