Yes you can turn wood on a metal lathe. However there are some consideratios you need to be aware of before you decide if you want to.
First is the speed. Most metal lathes do not run as fast as wood lathe. The bigger the metal lathe the slower the top speed. So Iwould check to see if it will go fast enough for you.
Secound is the cost of tooling. The wood lathe tooling like chucks and tool post do not fit on the metal lathe. These parts for the metal lathes are a lot more expensive.
Third is oil. A metal lathe has high persion mating surfaces like the saddle to bed and require oiling to keep them running smooth. All this oil will some day get on something your turning and possably ruin it.
So the real question is do you want to turn wood on a metal lathe. I would, but I am familiar with both lathes and have a machine shop to make anything that I needed to adapt the metal lathe for wood turning. Do I turn wood on a metal lathe? No, I have used the metal lathe to drill a long hole in wood, like for a pepper grinder. If I got a really good deal on a small metal lathe then yes I would drag it home mainly for metal turning. I might turn wood for something special on it but my primary wood turning would still be on my wood lathe.