.net/sql server creating abstract object layer architecture

I have a a broad-scoped architecture question. I have multiple .net projects and multiple databases all interacting with each other across multiple web applications all for internal use. We would like to create an over-arching layer, somewhere, somehow, to create objects out of the data we query from a database. These objects would have functions/methods available to them, defined somewhere. The question is, what is the most efficient, flexible and advantages/disadvantages of way to define these objects.

For example. Let's say I have multiple HR-related tables: tbl_employees, tbl_departments. When I pull an employee into an application, I then have a whole bunch of code in that project that is associated with that employee, most predominately the functions I can do to that employee - functions such as edit_contact_info or increase_salary or add disciplinary_note. Similar with a department and functions such as edit_department, manage_department_employees. Some functions may include some logic in them, some may just redirect to a particular page.

My question is, how or where or what can I make to classify an employee entry or even series of employee entries as an "object", meaning whenever I pull that "object" somewhere, I also have the associated actions with it. Whether I am pulling the data as a list somewhere or even as part of a data-visualization, I would like to have the appropriate functions/methods available. Even if it is in a different project.

I am looking for different possibilities, not necessarily one answer and I am not entirely sure the best way to go about it although I have thought maybe about creating another layer within the database that holds all the "object" definition data or perhaps some definitely with the .net framework but I lack the expertise to know exactly what I am talking about. From my limited knowledge, I believe I am looking for some sort of ORM (maybe in-memory) implementation, but I am not sure how to get started exactly.

Does anyone have any ideas or a direction to point me in perhaps?

I appreciate any and all help!

Edit To be clear, what I am trying to find is something I can apply on top of projects and applications I already have up and running and that are being used. I would like a way to implement this over-arching object functionality on top of pre-existing mvc projects