Nvidia proprietary drivers not showing up after install

For some reason, Nvidia proprietary drivers are not showing up in the list after a clean install (minimal). Can anyone tell me why? The 435.21 drivers (recommended for my card) do not install manually, either. Thanks for any assistance.

If you see that screen that you posted, select the newest one at the top, and then apply it. Then make sure that your Software Settings receives updates from the Main Server. You will need to do a restart of your machine after changing from the nouveau drivers. You are also advised to update your installation afterwards so that once the updated kernel has been installed you should then be able to get updated nvidia drivers through software updater in future.