Take advice from specialists or landlord before starting repairs to your business. Most of the repair work after flooding will need to be undertaken by professionals appointed by your insurers.
Think about how you can make your property more resilient to flooding during the repair process. This is something that you can discuss with your insurers, as there may be opportunities to factor in resistant and resilient features.
There may be funding available to help you install PFR and increase your flood resilience.