How do I kill a process and how do I make it run more efficiently

Thanks for reading this.
I am very new to butterfly and ladybug and grasshopper and sorry if this is a dumb question but how do I kill a process?
I am following the outdoor airflow example and between meshing and running and postprocessing 90% of my time is spent waiting for the process to finish, only then to change an input and run it again.
The question is whether I could kill the meshing or the running or the postprocessing on the fly in case I deem it to be taking too long?
Further, can you give me some pointers on how to run models more efficiently? I have a relatively new (2y old) laptop with 6 cores 12 processors and have been trying to use these to their full potential, mindful of parallel duty on segmentation but found that regardless of these efforts it only uses up to 20-25% of the CPU time; same goes for memory usage.
Thanks all,

CFD simulation is resource intensive. There are a number of different cloud services that can help you in such cases. SimScale is one of them that has a generous free tier.