First, study the problem of pothole detection. A search for "pothole detection system" turned out several scientific papers about it. You will find that it is a complex problem, requiring (at least) image conversion, video analysis, and interfacing with a movement sensor.
Once done with the papers, choose your platforms: a mobile phone mounted on a car? Specialized hardware? Arduino mounted on a motorbike? Any other? Depending on your choices, there can be ready-made libraries for what you need. You will need programming to tie the libraries together.
Good choices of language (for speed) are C and C++, if you can use the libraries with them. Else, learn the supported programming languages.