How to echo a value of a var stored in another variable?

I'm writing a shell script in AIX and using ksh.

I have a scenario where I have a variable A which stores $B.
so when i echo "$A" it prints $B

But I wish to print value stored in var b ie. \a\dir\res\

I wish to store \a\dir\res\ in a third variable C.
later I want to cd into that path : cd $C

How can I do it.

Not sure I understand what you're after, and not sure either if that sort of redirection is the best way to do what you want.
You might want to try using eval to evaluate / expand variable twice, but this has its imponderabilia attached to it and may become dangerous, so be sure what exactly you're doing.
Another option is a sort of redirection that ksh offers, using ${!vname} expansion.