Create roles and permission along with user permission restriction

I want to create roles and permission in such a way that one user will only be able to see data related to that user only. Ex- Student1 will be able to see all data related to itself.

User-permissions I know but need help with more than 1000 students.

User Permission will help for this case

I need to then creat for each of the 1000 user and for each documents…

You can try data import to import these user permissions.

Can you provide an example? With images, if possible.