Adding prerequisites section

Author: rnaskulwar

README.md

@@ -14,7 +14,7 @@ VPF works on Linux(Ubuntu 20.04 and Ubuntu 22.04 only) and Windows
   - [Compile FFMPEG with shared libraries](https://docs.nvidia.com/video-technologies/video-codec-sdk/12.0/ffmpeg-with-nvidia-gpu/index.html) 
   - or download pre-compiled binaries from a source you trust.
     - During VPF’s “pip install”(mentioned in sections below) you need to provide a path to the directory where FFMPEG got installed.
-  - or you could install system FFMPEG packages (e.g. ```apt install  libavfilter-dev libavformat-dev libavcodec-dev libswresample-dev libavutil-dev on Ubuntu```)
+  - or you could install system FFMPEG packages (e.g. ```apt install  libavfilter-dev libavformat-dev libavcodec-dev libswresample-dev libavutil-dev``` on Ubuntu)
 
 - Python 3 and above
 - Install a C++ toolchain either via Visual Studio or Tools for Visual Studio.