Step1: Login

Simply login into your cCpanel

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Step 2: Navigate to File Manager

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Step 3: Extract

Go to Magento Root Directory in the file manager, Upload Zip file on Magento Root Directory and Extract

upload and extract

*If the zip file has step1/ and step2/ folder in this case you need to copy the files from step1/ into your magento root directory first and then files from step2 folder