I need a program for converting tcsh script to bash one.
Does anybody have it this tool?

I don't think a tool like that exist, due to all the nuisances the tcsh language holds. Furthermore, it would require human intervention to check the result at the end of the translating process (unless one accepts the translation as it is and runs it at risk of scrambling the entire system). Hence the best bet is to gain a good knowledge of the tcsh language, trying to interpret what the script exactly does. Then, one can freely translate it in another language.

Just out of curiosity, what this tcsh code is supposed to do? How many lines of code are they?

that "tool" is called a human being. learn about bash, and do the translation manually. that's the best way to go.