If the email status is either 'Created' or 'Sending', the delete and resend buttons are disabled in the control that displays the email queue. For reference, this is in
CMS_Modules\EmailQueue\Controls in the method
As a Global Administrator, you should not need any additional permissions to delete or resend emails.
Ensure that your system is correctly configured to send emails by checking the SMTP settings and that the scheduled tasks are running. You can find out a bit more about this on the 'Sending e-mails' page on the Kentico docs.
If everythign is configured and you can send (and receive) a test email, it's worth checking how long the emails have been in that status for. If they've been there for a while it would point to something going wrong in the process that has led to the email getting stuck.
If you have access to the database, look in the
CMS_Email table and see how old the
EmailCreated dates are. You may be able to tally these up with errors in the event log to get further information as to why they have failed.