Simple Word Advantage of Stored Procedures is:

*Store procedures can reuse the execution plan.
*Store procedures can reduce the network traffic.
*Store procedures can code re-usability and better maintainability.
*Store procedures can provide better security.
*Store procedures can Avoids SQL Injection Attack.

Difference Between Procedure Vs Stored Procedure?

The only difference between a procedure and a stored procedure is
where it is stored and how it is called. A procedure is stored within a
procedure or an anonymous block . A stored procedure is stored in any
schema in a database.

Also

Stored procedures provide a powerful way to code application logic that
can be stored on the server. Procedure can write anywhere in PLSQL.