cPanel has synchronization and calendar functions, see in your cPanel / section Emails / Calendars and contacts, you have the access info CalDAV and CardDAV.
This works from the email account via webmail, Roundcube see at top : calendar, and not the reverse with an external source.
And it seems that it works with IOS, the rest being not guaranteed for other systems to date.
Articles to read :
https://documentation.cpanel.net/display/CKB/How+to+Set+Up+Calendars+and+Contacts#ca73d605b3d449fba68e93dec9725d2b
https://www.namecheap.com/support/knowledgebase/article.aspx/9272/2171/how-to-configure-caldavcarddav-on-android
https://www.slipstick.com/outlook/sync-outlook/syncing-outlook-with-an-android-smartphone/