Hello @srikar_26
For a variable to be seen in the FreeMaster directly with his name, it has to be declared a Signal Object Class as "Exported Global" or "Volatile" if you use it in an interrupt as well. Otherwise, Simulink will declare the variable inside a structure starting with the model's name.
For that, depending on the Simulink version, you have to the to the Model Data Editor and select the Storage Class.

Hope this helps,
Marius