There are several Blueprint maps located inside the Content Examples project that demonstrate the power and flexibility of the Blueprints system. Whether you are looking to define player controls, implement a health/pick-up system, or simply have a door that opens when a player approaches it, the examples illustrated in these maps should give you some ideas on how to approach whatever it is you are after.
This page indicates what examples are included in each map and where to find them so that you may jump to your area of interest and begin scripting right away. If you are new to Blueprints however, it is suggested that you begin with the Blueprints_Overview map as it will cover the core aspects of the system and will help get you started with using them.
You can find additional resources on how an example was constructed (if applicable) by clicking on the example's name in their respective tables.