The problem is that there may not be a such a thing as $fvalue{3}. More precisely, hashes are not indexed by numbers, but by keys (strings).

You may want to store your values in a real array. But then you should discard the keys. Or else you may want an array of arrays (AoA), each of which containing the key and the value. Or a HoA or an AoH. Who knows?!?

You may also want to push your keys into an array for "sequential" retrieving. But then again, who knows?!? All this smells byzantine and suggests you may have an "XY problem": you are asking X, but you really want to do Y.

I ask you to trust me when I tell you that this is "very" x 10 basic perl. I recommend reading some basic {introduction,tutorial}...