Good evening Krishnareddy,
Are you referring to the timeout property?
Create an int32 variable named int_time and set the amount of time you want in milliseconds. Place that variable in all the activity TimeoutMS property.
You could also enter that value in the config file (on the constants tab) and retrieve the variable and value from the config file as a dictionary key value pair using the same functionality as the REFramework.
Credit for this answer goes to @Palaniyappan :