Hi @Dirk,
Thank you for your question and welcome to the Bunnings Workshop community, it is fantastic to have you with us.
I'd suggest you have a look through the Bellessi Installation Instructions which state that their panels can be cut with a circular saw. It should be fully supported using sawhorses and a flat material such as plywood to support the weight while cutting.
You can then use a straight edge and clamps as a guide to get a nice straight cut.
For holes, you can use any standard drill bit but be aware that drilling through plastic will blunt the drill bit quickly. For larger round holes, use a holesaw.
To attach to a chipboard backing, make sure the surface is nice and clean by using sugar soap and a soft cloth to wipe any contaminants from the surface. You can then use a clear neutral cure silicone such as Selleys Translucent Interior Neutral Cure Silicone to adhere the splashback to the chipboard.
Let me know what you think and if you have any further questions, please don't hesitate to ask.
Jacob
