When adding Campaign Members to your Soapbox Mailer Campaign, you typically should be able to view all the Soapbox Mailer related Campaign Member statuses, including options like "Targeted", "Sent", etc. If you're unable to see them, it's likely that your Campaign was not created with the record type "Soapbox Mailer" and the Campaign Members type not selected as "Soapbox Mailer" as well.
To fix this, simply create a new Campaign with record type "Soapbox Mailer" and with Campaign Member type "Soapbox Mailer". Doing so will tell the Soapbox Mailer app to ensure the new Campaign allows for Campaign Member statuses that it needs, like "Targeted" and "Sent".
Happy emailing!