Is a monkey a vertebrate or invertebrates?

Yes.

Any animal with a backbone (spine) is a vertebrate. That includes all mammals, reptiles, fish and birds. It excludes living creatures like worms, insects, ants, bees, sea urchins, jellyfish etc.

Monkeys have spines and they are therefore vertebrates.

yes a monkey is a vertebrate because humans originated from apes so they too have a backbone like us! So it is a vertebrate!