Before you proceed, you need InTouchApp installed on your phone.
How to Import contacts to InTouchApp?
Step 1 - Open web.whatsapp.com in the browser and Scan the QR code by using WhatsApp on phone.
Step 2 - On the top left of the screen, beside the display picture, click on a red plus + icon > select Import Contacts.
Step 3 - Click on Choose File button, then browse & select the file (csv, xls, xlsx, vcf). Make sure the imported file has to match the supported file formats. You can view the sample files.
Step 4 - Click on Upload button. Your contacts will be imported shortly.