lscpu
#or
cat /proc/cpuinfo
nproc
# 8
sudo apt update
sudo apt install python3-pip
sudo pip install s-tui
s-tui
# nproc
You can still do this in top.
Run the `top` command, and then press '1' on your keyboard. This will show CPU usage per core.
Limit the processes shown by having that specific process run under a specific user account and use Type 'u' to limit to that user