If you select PST as your output option, then it will show you this screen:
Now, hit on Change option and choose saving path to save resultant files where you want.
After selecting destination location, press on Export button to initiate the conversion procedure of vCard files to PST format. You can view live conversion during the process.
Once the whole conversion is finished, a pop-up window will appear showing the message like Conversion is Done. Then, press on the OK button to accomplish the process.
After clicking on OK option, the software will enable View Log option.
Navigate to the folder location of your resultant files and click on the folder to open and access the resultant files
Now open PST files in Outlook by clicking on File >> Open & Export >> Open Outlook Data File. Select the PST file and click OK button.