First, second and third person is about writing from different perspectives. The personal pronouns can be divided into three groups as follows:
Next time you are reading a book, take note of which person it is written in. You may find the whole book is written in third person or that some chapters are in first person and so on. You could also try writing three pieces - each in a different person. This will really improve your English skills.
Do this 11-plus quiz and get comfortable with 'person' and learn a few quotations too.