how can i set permission to a player in a specific plugin?

See Permissions

And https://umod.org/documentation/api/player#grantpermission

Please read https://umod.org/documentation/plugins/permissions for information about permissions. If you are still unsure about something afterwards, please elaborate on your problem and we'll try to help you out.

thanks you very much, i got it perfectly, the thing is, i´m new in this stuff, can i make you a question?

If your question is unrelated to this thread/subject, please open a new thread in the appropriate category. Otherwise you can post your question here.