How do I parse out n to a var named $nvar?

I'm either confused or failing to understand your question, but is a simple search and replace what you want to do here? In which case, you'd be looking at this code:

my $function = 'b+c(t)+t^234.57*t^n*f(t)+Z';
$function =~ s/n/\$nvar/g;
print "New function: $function\n";
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Which should print

New function: b+c(t)+t^234.57*t^$nvar*f(t)+Z
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In case I got you wrong, however, could you please clarify your question? ;-)

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