Hi yusufyoruk,
I can’t find any UE4 tutorials on creating a Custom Character Menu yet. It is a rather complex feature to implement. There is a similar discussion on the forums that you may be able to restart.
If you are new to UE4 please take a look at our Wiki. We have tons of written tutorials and videos explaining how to create features in Blueprints and code.
Another suggestion would be to look for tutorials from UDK/UE3. Just make sure to take them with a grain of salt because a lot has changed moving to UE4, but it may give you a few ideas.
I hope that helps.
Thanks, TJ