The error message says something about configuration and “cron job”. I have never managed our organizations emails so I am clueless about how to fix the problem. Talk to me like a 5 year old. Our tech person is currently out of commission.
Without the full error message it is hard to understand what you need to do. I'll try to help with the basics.
Go to Civicrm home page menu item Administrator > then drop down to > Administration Console > configuration checklist > "From Email Addresses" Click to add from email addresses that you should already have setup and access to through your hosting/domain provider.
Now check your system status: Go to Administrator > Administration Console > System Status and verify that you have only green status on "Cron Running OK" with no warnings. If all green go to Administrator > System Settings > Scheduled Jobs and verify that your mailing jobs are enabled. I recommend you visit the Civicrm Documentation User Guide and search for Cron Jobs to understand what each one does, but enable at minimum "Send Scheduled and Send Reminders."
Now test and see if you can send the emails with no errors. I hope any of this helps.