>Good afternoon,
>I need in the main of the program to create a timer on the screen that every 15 minutes executes an operation for me, while the application is running.
>Can someone help me.

Beyond what Al said, if you need those tasks to happen only if the user isn't doing anything at the time, then check out the section "Monitoring user activity" in this paper: http://tomorrowssolutionsllc.com/ConferenceSessions/Bind%20Events%20for%20Better%20Applications%202017.pdf

Tamar