The best way is to first convert your CSV file into a VCF file using Softaken CSV to VCF Converter. After that , log into your iCloud account, go to Contacts and use the import option to upload the VCF file. All your contacts will appear correctly in iCloud with names, phone numbers, and emails. The converter keeps all fields clean and organized. I used it to move my Outlook contacts into iCloud and it worked perfectly . No missing data or format problems. It also handles duplicate entries automatically. The free trial version lets you test a few contacts before doing the full conversion.