siemens simatic s7 instruction help

I will be the first to admit I am not very good with Siemens software, and my question may be simple to someone who is. I am working with a Siemens s7-200 processor, programming software is STEP7-MICRO. my question is I am trying to lower a temperature set point from a low of 140 to 100 what instruction is this in? A pid?

Use PID wizard, to learn how to change setpoint of a process.
I dont recommend start learning from PID, its complicated, very difficult to find proper parameters.