The MINISTRY OF COMMUNICATION AND INFORMATICS, a government department, run a database that automatically includes everyone with an identification number (NIK). There is no public access to this database other than as mentioned later in this post.
Foreigners without a NIK can apply for registered using this government site, but they can't register themselves.
https://vaksinln.dto.kemkes.go.id/sign/in
The MINISTRY OF COMMUNICATION AND INFORMATICS has a site you can use to access your or your family's information. You may also download certificates from this site.
https://www.pedulilindungi.id/
The ministry have a free to download app
https://play.google.com/store/apps/deta … tracencare
I recommend downloading the app but I have yet to be asked to use it
The app is not required for intercity trains as KIA have access to the database so they know your status as soon as you book your ticket.
If someone has experience (Actual, not googled) of an airline or ferry, it would be nice to hear from you.