Materials for mould and model

I want to make a solid model that needs to be strong with my Snapmaker 2.0. What materials should i use for the mould part? I currently have PETG, PLA+ and TPU95 filament.
And what process steps should I use.

Can you explain a bit more? What exactly are you planning to pour into the mould?

Perhaps this gives you some ideas: https://www.youtube.com/watch?v=Zo_tgWfUg2A

But if you want to peel off the mould, flexible materials would be a better choice.

Obviously: if you want to cast something hot, no material you can print will be working. But you may CNC mill something - one of the projects I’ve in the pipeline to mill soapstone moulds for coins cast from tin - I did this by hand, but plan to do so with CNC milling.