UML Class-Diagrams : class inheritance and relationships between classes

I’ve never made a class diagram before, that’s why I tried to ask. I always learn from my mistake. I have read some references, but I am confused how to test the results I made? because this is not a coding which if have error, the error message will be appear. My case is Monthly Report Archiving (Web-Based)

this my design database
https://i.stack.imgur.com/w4WwK.png

and this is a class diagram that I made based on design database.

is the method for creating class diagrams similar to erd? I am very confused how to inherit the class and which arrow should I use? in the path that I made there are three users. and each has a different role

  1. Public Relations = Input data from external user (the applicant comes and gives a written proposal) then the data is stored in the database. The data includes applicant data and proposal data. PR can also see data that has been confirmed by the Division
  2. Division = The division can see data that has been stored by PR and confirm the data. Data that has been confirmed will be filed and made a report.
  3. Manager = can only see reports