If you mean the fonts you create, then sure! It’s just an editing program, in the same way you’d use something like Photoshop. The program doesn’t do any creative work, so you’re the creator of the font.
So in the same way that image editing works, if you create something from scratch, it’s your own creation so you can do anything you want with it, while if you take something already made and modify it, then it becomes more complex.
In any case, the fact that you’re using this tool in particular doesn’t matter, it works the same way as with other creative products.