Hi
There is no Fire effect with VP but you could experiment a bit by downloading some green screen flame effect clips from the internet and trying these out. Another approach might be to download some transparent png images of flame series that could be used as overlays in front of and behind whatever you object you want to "burn" There are also animated gif images that come in series that together will make an animation of moving flames but as individual images, even if they have transparent backgrounds, you would probably have to convert them to jpg images and then green screen them. This is because single gif images are seen as single frame clips in VP and can't be usefully used.
Here is a VP screen shot of a VERY crude example using a set of animated cartoon flames from a jpg flame set, green screened over a teddy bear. (Sorry if you love your teddy Bear 🙂) You should be able to do much better with REAL flame video clips....
You will have to experiment I think.
Nat