Problem installing Nvidia drivers to work with cuda

I am using Ubuntu 20.04 and trying to install cuda drivers.
nvidia-smi
NVIDIA-SMI has failed because it couldn’t communicate with the NVIDIA driver. Make sure that the latest NVIDIA driver is installed and running.
nvidia-bug-report.log.gz (115.3 KB)

sudo ubuntu-drivers autoinstall gives these errors

WARNING:root:_pkg_get_support nvidia-driver-510: package has invalid Support PBheader, cannot determine support level
WARNING:root:_pkg_get_support nvidia-driver-510-server: package has invalid Support PBheader, cannot determine support level

$ ubuntu-drivers devices
WARNING:root:_pkg_get_support nvidia-driver-510: package has invalid Support PBheader, cannot determine support level
WARNING:root:_pkg_get_support nvidia-driver-510-server: package has invalid Support PBheader, cannot determine support level
== /sys/devices/pci0000:00/0000:00:01.0/0000:01:00.0 ==
modalias : pci:v000010DEd00002484sv00001028sd00003907bc03sc00i00
vendor : NVIDIA Corporation
driver : nvidia-driver-510 - distro non-free
driver : nvidia-driver-465 - third-party non-free
driver : nvidia-driver-470 - distro non-free recommended
driver : nvidia-driver-510-server - distro non-free
driver : nvidia-driver-470-server - distro non-free
driver : xserver-xorg-video-nouveau - distro free builtin

Moved to CUDA Setup and Installation