How can I delete q duplicate person when it appear there that "this person cannot delete"?
From the screenshot, I can't tell which one applies, but in general, in the shared tree you correct problems by merging (not deleting) duplicates or removing relationships (not profiles).
It appears that there is only one Roman Pacong Derita, but he has a child who has two sets of parents. The one set of parents includes both the father Roman Pacong Derita and the mother Avelina Almen. The other set of parents includes only Roman Pacong Derita with an unknown mother.
Assuming that Roman Pacong Derita and Avelina Almen are indeed the parents, the way to fix this is to go to the child's person page, and in the Family Members section, click on the pencil edit icon to the right of that child under Roman Pacong Derita and the unknown mother. Then you can delete that partial relationship, leaving only the complete relationship with both parents.