sudo apt search nvidia-driver

For example,

sudo apt install nvidia-driver-470

or

sudo apt install -y nvidia-driver nvidia-cuda-toolkit

returns:

┌─────────────────────────────────┤ Configuring xserver-xorg-video-nvidia ├─────────────────────────────────┐
│                                                                                                           │
│ Conflicting nouveau kernel module loaded                                                                  │
│                                                                                                           │
│ The free nouveau kernel module is currently loaded and conflicts with the non-free nvidia kernel module.  │
│                                                                                                           │
│ The easiest way to fix this is to reboot the machine once the installation has finished.                  │
│                                                                                                           │
│                                                  <Ok>                                                     │
│                                                                                                           │
└───────────────────────────────────────────────────────────────────────────────────────────────────────────┘

sudo reboot -f