Media portal supports both standard certificates and Let's Encrypt certificate. For standard certificates, you can create a certificate signing request (CSR) to send to your certificate authority first, and then upload your certificate or you can just upload your certificate if you completed the CSR process outside of Media portal.
To manage your certificates, you’ll need to navigate to the “Manage Certificates” menu of your Service Component ID (SCID). To do this, sign into Media Portal, select My Services > Caching from the tab across the screen, and from the lists, select the access group and SCID you’d like to work with. click on “Manage Certificates” to open the menu. Media portal lists the certificates associated with the SCID you selected, and the states of the certificates. Certificates in active state are ready to use; certificates with other states may need your attention or may still being processed. To view details for a certificate, on the row for the certificate you want to view details for, click the linked certificate name. Media Portal shows details for the certificate. If the certificate has pending changes, you can toggle between the active certificate (Current tab) and the changes (Pending tab).