How customizable is xWiki? Create new tables, attributes and relationships

Hello everyone!

I have some question about how customizable of xWiki source code.

That’s because of the following: I want to add new fields in order to add new attributes when a page its created, for example: Category, knowledge level, or another attribute.

2nd question:
Is there any tutorial guide or video on how to set up the project in Eclipse, NetBeans, IntelliJ IDE… in order to change the sourceCode?