Yes you can eat an orange that has a bit of mold on the orange.
When you have an orange that has a bit of mold on the orange all you need to do is just remove the moldy parts of the orange and then you can safely eat the rest of the orange.
Although if the orange you have has a lot of mold on the orange then your best best is to just throw the entire orange out.
However if the orange just has a slight bit of mold on it then you can cut off or peel off the moldy portion of the orange and continue to eat the rest.
The same is true for other fruits and even vegetables and if they just have a bit of mold on them all you need to do is just remove the moldy parts of them and then eat the rest.