Hi @Gunjan Bhure,
From this thread: Create file in SPO document library using HTTP request, I found an answer which may help in this case:
This is probably too late but may help others. Looking at the picture you are converting the base64 string to a binary, just pass the base64 string of the file contents, I have done this request in power automate just fine with the base64 string.
By the way, Power Automate is not currently supported here on Q&A. The product group and experts for Power Automate actively monitors questions over at: https://powerusers.microsoft.com/t5/Microsoft-Power-Automate/ct-p/MPACommunity.
As we are not quite familiar with Power Automate, we suggest you post a new thread in that dedicated community.
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