How to Install Demo data manually in CoverNews Theme

Dear Team,

I am trying to import demo data. i have downloaded demo data zip file from theme provider website but everywhere even on youtube it is showing just import in one click but in my WordPress there is not option coming. its showing MANUAL DEMO FILE UPLOAD. There is three option coming (1. Choose a XML file for content import:)
(2. Choose a WIE or JSON file for widget import:) and (3. Choose a DAT file for customizer import:) I have only 1 zip demo zip file. How can I upload the file manually? Please help me out on urgent basis

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