I'm not sure what you mean. ISPConfig saves its configuration to the database and system config files when you click on the save button in a form or when you switch the tab of a form. Or do you talk about backups?
I backup the sites here on by ISPConfig /var/backup/web1 /var/backup/web2 I wanted to know if it was also possible to backup the ISPConfig configuration here /var/backup/ispconfig
There is a new feature for this in the upcoming 3.3. version: https://git.ispconfig.org/ispconfig/ispconfig3/-/issues/6824