You can import your PST file to Outlook by manual method, follow below steps: -
- Click File tab in Microsoft Outlook
- Select Open & Export then Open Outlook Data File.
- Select Import from another program file then click Next
- Now open PST file and click Next
- Now type the path of your PST file or you can also browse it.
- Now select the folder that you want to Import
- Click Finish.
If above manual method doesn't work, then you can download any third party tool. I hope my answer has helped you learn to import your PST file.
Please mark as "Accept the answer" if the above method helps you.