If you're looking to use the VSPL EML to Office 365 Converter tool to convert email content, here's a brief guide:
Install and Open the Tool: Download and install the VSPL EML to Office 365 Converter tool. Launch the application after installation.
Add EML Files: Click on the option to add EML files. Browse your system and select the EML files you want to convert.
Select Destination: Choose Office 365 as the destination. You may need to log in with your Office 365 credentials.
https://www.vartikasoftware.com/product/vs-eml-to-office365-converter.html