This is a pretty broad question that I don't think can be answered with the information provided. Hopefully I can help at least a little bit.
Q: How do you submit the c program?
A: Looks like you already submitted it correctly, [ qsub someProgram.sh -l walltime=x....]
If you want to interact with the program while it is running, then look at interactive jobs.
http://docs.adaptivecomputing.com/torque/2-5-12/help.htm#topics/commands/qsub.htm
Q: How is load balancing done on the compute node?
A: Torque does not do any load balancing (exception is mom hierarchy ). Here is the life cycle of a job:
1. job is sent to pbs_server from the submit host
2. pbs_server sends the script to 1 of the nodes (called the mother superior)
3. The mother superior executes the script and queries the other nodes through the TM interface. (The job does not actually run on every node)
Q: What configuration do you have to do in the cluster?
A: Too vague.