Cameras are child's play to make, the hard part is making the action look good. Scripting combat to go one way can be very difficult. Also, you need to have a sense of what camera angles will look good. Basically, to make a camera script you:
1. Make a camera.
2. Move it around, play with its FOV, etc. while stuff happens or your script makes stuff happen.
3. Delete the camera, end cutscene.
One catch with OFP is that there are a number of very cool features that really add power to your cutscenes, but you need OFP 1.85+ to use them. I'd recommend getting Resistance, it isn't a very large sum of money for it and you can get a lot of fun for your cash.