Exporting / copy data from Vertica DB to a MS SQL DB

Few options:
Vertica offers several integration tools such as SSIS, OLEDB and ADO.NET components, and so on to support MS SQL databases. Please see documentation at https://www.vertica.com/docs/9.3.x/HTML/Content/Authoring/ConnectingToVertica/InstallingDrivers/Windows/MicrosoftComponents.htm
Another option is an ETL tool such as the freeware "odb" supplied with Apache Trafodion that can create ODBC connections between Vertica and MS SQL and copy tables and schemas.
It may depend also how often you need to move data between tables, and how many tables you need to copy. The simplest way to copy a single table is probably to use vsql to export data to flat file, then osql (MS SQL native) or isql (ODBC) to import the flat file data into MS SQL. This might be tedious but easy to set up for one-time, single table transfers, or even a simple export/import script for a cron job to copy data regularly.
So, it might help to know more about your use case, for example one-time or recurring transfer, and whether you need to export all data or just new records.