Fixture has 3 hanging lights, each light has 1 green, 1 white and 1 black wire. There is also a bare copper wire on the base of the new fixture. How do i properly attach the green ground wires and the bare wire?
You can wire them the same way you'd wire the white wires together and the black wires together. If there's a green or bare wire coming out of the ceiling connect it to the group of ground wires too. Use standard wire nuts or something similar to the below illustration if in the U.K.