If you have saved your contacts in CSV format, and now wish to export them to VCF format, it is an easy process. You will need a program that can read a CSV export and then export your contact to vCard (.vcf) format.
Softaken CSV to VCF Converter is a good source that will work on all versions of Windows 11, 10, 8.1, 8, 7, etc. This software is able to read CSV files from Excel, Outlook, Google or any other CSV files created. You will load the CSV file, do the mapping of field names like name, email, phone, and then export the contact as a single or multiple VCF file. It also works completely offline and provides a free demo that will convert a limited number of contacts for a few to test the program.