You can, however, import passwords from either Firefox or Chrome.
So if you’ve got a CSV file from another password manager and you don’t have either of those browsers on your machine, you’ll have to install one of them first and upload your passwords into it.
One note: I had a series of mishaps trying to import from Firefox into Safari.You can check to see if the import worked by going to Safari’s top menu and selecting Safari > Preferences > Passwords