Need access to /proc/sys/net/core

You run the containers, but of course, the files are not there for the same reason what I replied to your other question

You have a virtual machine, but in this case, even if you could share the folder with the virtual machine, wouldn’t work, as that folder is not a normal filesystem, but a way to communicate with the kernel. So the solution would be to use Docker CE and not the Docker Desktop with its virtual machine.