Is turtles invertebrates

Nope. Turtles got spines.

The inner layer of bone is fused with the usual bony structures associated with all vertebrates, the

vertebral column and ribs. The vertebrae are particularly interesting for the modifications that have occurred. The vertebrae of the neck and tail are small, allowing for a high degree of flexibility, while the vertebrae of the central portion of the vertebral column are enormously elongated and inflexible, fused with the bony layer of the shell, acting as a support for the carapace.