What is the current version? If it is 9.1 then how can I upgrade to 10? Should I uninstall the current CUDA and then update or can I parallely install another version?
Also I would like to know the steps in detail for it.
nvidia-smi is part of the driver package. The CUDA version number it shows is the highest version of CUDA (11.0) the current driver (450.51.06) supports. nvidia-smi won’t tell you anything about installed CUDA version(s).
The fact that nvcc indicates version 9.1 would suggest that CUDA 9.1 is installed. Whether any additional CUDA versions are installed, one cannot tell from this. Strictly speaking, one cannot even tell from that whether a complete and fully functional CUDA 9.1 is installed, although that is likely.