You can uninstall the .NET Framework 3.5 using the "Add or Remove Programs" feature in the Control Panel.
If you have a Windows installation media (like a USB or ISO) in your drive, you can use dotnetfx 365.exe
Before we dive into the blog post, it's important to clarify a key technical detail: a file named exactly does not exist in Microsoft’s official .NET ecosystem. You can uninstall the