Deep Learning with Keras. Classification problem with large data
There are actually a lot of examples out there which show how to apply Keras to different types of data. A really good source is F. Chollet's book "Deep Learning with Python". The code is online. You could start with the tutorial on predicting house prices. It is a regression problem, but you can easily change it to a classification problem. 

A general remark: Neural nets (such as Keras) usually work well with very complex data (images, sound, text). For "normal" data, other approaches are often better suited (e.g. boosted trees). However, with the large number of features you have, NN is worth a try.