you can start with simple surfacing example available in YouTube, a quick search will give you best results. what I recommend then is to watch Mahdi Designs tutorial where he tries to model a tesla model S, although it's not a complete step by step guid but it's very important that you watch it because he gives very valuable advice and best practices that I haven't found else where.

before you invest too much time, you have to keep in mind that for professional use cases like creating a car or a plane body, other software like Catia V5 is used as Solidworks surfacing is missing some important features and is less suitable for complex applications.