you should consider a dispatch-table/-hash to do the dirty work done via if-statements: (the seclev stuff is only there to show some further benefits beneath readabilty-enhancement :)

my $apps = {
    help => {
        app => '/main.html',
        seclev => 0,
    },
    staff => {
        app => '/cgi-bin/staff'
        seclevel => 0,
    },
    adm_staff => {
        app => '/db/staff/selstad.pl',
        seclevel => 10,
    },
    birthday => {
        app => '/db/staff/birthday.pl',
        seclevel => 10,
    },
    jubilee => {
        app => '/db/staff/firmenjub.pl',
        seclevel => 10,
    },
    location => {
        app => '/db/staff/location.pl',
        seclevel => 10,
    },
    
};
my $app = $q->param('app');
$app = 'help' unless exists($apps->{$app});

my $application_to_call = $apps->{$app}{app};
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