Hello, you should disable watchdog from the Configuration Utility by pressing F11 after reboot the server, then in Configuration Utility you need to set the BOOT type to UEFI , save changes and then reboot the server.
Press again F11, enter into the Configuration Utility and then disable watchdog, Set BMC WDT Support For POST and BMC WDT Support For OS to Enable or Disable. I have also attached some pictures.





In the end , save changes and reboot the server to take effect, and try again to install the OS. Hope this help.