Well, where does the file exist? What is the working directory of the script you are running? Try:

use feature 'say';
say for <*>;
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This code will print all file names in the current working directory of the Perl program running, and you will be able to see whether Perl can see this file there, or not.. Perhaps your file is actually in another directory. You can use @ARGV to get the file names from the command line parameners instead of hardcoding them in the script. You can also use Cwd to get the current working directory and use chdir to change it (usually it's not needed).