Customized Version

Dear all, I`m beginner with LEDE, and now I have a new project that I need do a customization in a few things, after saveral days of testing and google search I don't know where I can do this. I need just customize:
Hostname
Firmware Version
brand

and change the default serial baud rate, I don't know where I can found this settings in my source code.

Anyone can help me with this?

Thanks and best regards!
Tadeu Ribeiro