Just my two cents for a really basic setup:

• For two nodes, depending on the computing power of each individual machine, a 1Gbit/s network may be sufficiant.
• You would simply place them in the same IP network
• Maybe you would realize passwordless ssh by e.g. sharing ssh-keys between both machines.
• You would need MPI (e.g. OpenMPI) and a MPI compile of your desired application at the same pathes on both machines. Using a shared drive may be of interest.
• You would finally run the MD by something like (openmpi example): /path/to/mpirun -n 16 -H node1,node2 /path/to/mdprog md.in
• If both machines are different in power and number of cores, the MD engine requires a load balancer. Also MPI launch options may be different.

I personally would also install the SLURM queue, usually available from apt-get. Having a openmpi with slurm support then, allows easy parallel job setups at submit time, while the commandline to start the program would only require "/path/to/mpirun /path/to/mdprog md.in". Also multiple jobs could be organized like that.

I will try all this. Thank you so much. If possible, can I get any tutorials!(I am really new to this and have been learning on my own.) But still, I will try my best with what you answered. :)

I tried this https://www.youtube.com/watch?v=gvR1eQyxS9I and then https://www.youtube.com/watch?v=F8U4TrOlwEQ

The PVM was easier but not fruitful to me and got stuck with MPICH.

You surely find tutorials on how to set up a cluster, which do also apply on a cluster of only two nodes, however the effort may be much larger there ;)