Hello, Can I create my own fields for user, like in the Buddies plugin?

Yes, this is how you can extend your user, basically you can do anything https://www.youtube.com/watch?v=AomK1eYAq78 https://www.youtube.com/watch?v=gBGVOspf1NY

Watch these 2 videos.

Thank you. In the Buddies it is not so difficult. :)

From Profile plugin details:

Adds back end configuable extended information for front end users Unlimited, customizable text, textarea or dropdown fields with admin set labels and choices for user information.