As of December 31st 2022, the FDIC had approximately 126 billion dollars in its Insurance Fund. That is more than adequate to cover the approximately 20 billion dollars that were insured at Silicon Valley Bank. As for the uninsured deposits, the FDIC will pay a portion of the deposits and they will receive a receivership certificate. The FDIC will administer the Affairs of the bank liquidating assets and possibly selling some deposits. That will take time. The Securities portfolio is not marked to Market and there are likely loans tied to high risk Ventures such as Bitcoin. It is likely that the FDIC may have to rely upon borrowing money from the Federal Reserve or the US Treasury. If there are a cascading number of failures in the next few months, the FDIC will have to go borrow money.
since the beginning of the century, the FDIC has made depositors whole even the uninsured deposits. However if there is a Cascade of bank failures then the depositors will have to settle for a portion of their uninsured deposits.