If gravitational waves exist are they technically just another form of light/electromagnetic wave?

I would imagine a gravitational wave would have very similar characteristics to electromagnetic wave, what kind of differences are there?

Answer

If gravitational waves exist are they technically just another form of light/electromagnetic wave?

No.

Electromagnetic waves are (classically) disturbances in the electromagnetic field that propagate with speed $c$.

Gravitational waves are disturbances in the geometry of spacetime that propagate with speed $c$.

I would imagine a gravitational wave would have very similar characteristics to electromagnetic wave

Electromagnetism is (classically) linear. However, the gravitational field equations are non-linear (which are approximately linear in the 'small-signal' approximation).

While there is dipole electromagnetic radiation, the lowest order gravitational radiation is quadrupole. This is related to the fact that the gravitational field is a rank 2 tensor field as opposed to a vector field.

So, other than the fact that they are waves and propagate at $c$, they aren't similar at all. In a comment, Hassan has provided a relevant link for further reading.