(Disclaimer: not an expert, I read patio11 and Money Stuff when I'm pooping and that's about it)
This is, by and large, how it currently works today. Not that often do actual pallets of cash get moved from one bank to another; a lot more often, some centralized bank has a big ol' ledger, where various banks move money from one column to another. One of those centralized banks is The Fed, that's how the US was able to freeze so much of Russia's money; there is a bank account at The Fed, and that account is where Russia keeps its US dollars (or the bank that Russia works with keeps its dollars, some of which are Russian, or the bank that the bank that Russia works with... you get the idea).
The biggest difference between a CBDC is that there wouldn't need to be a printed dollar to back that ledger, so instead of rare pallets-of-cash movements, it would be entirely digital. Printing money would be an UPDATE statement rather than through a printing press.
This is, by and large, how it currently works today. Not that often do actual pallets of cash get moved from one bank to another; a lot more often, some centralized bank has a big ol' ledger, where various banks move money from one column to another. One of those centralized banks is The Fed, that's how the US was able to freeze so much of Russia's money; there is a bank account at The Fed, and that account is where Russia keeps its US dollars (or the bank that Russia works with keeps its dollars, some of which are Russian, or the bank that the bank that Russia works with... you get the idea).
The biggest difference between a CBDC is that there wouldn't need to be a printed dollar to back that ledger, so instead of rare pallets-of-cash movements, it would be entirely digital. Printing money would be an UPDATE statement rather than through a printing press.