if i type and run this (17, $var, "a string"); where will this be stored

It won't be stored anywhere,

, how can i access them , i haven't specified the name of my variable .

you can't access "them" that aren't stored , so it might be a good idea to store "them"

perlintro shows you examples of storing like  my @stuff = ( 17, $var, "a string" );