not sure I understood you.
I'll replace the generic condition and action names with a new example using sort of pseudocode:
+Enemy is alive
+Enemy is on ground
+Enemy is not attacking
+Enemy is near player
+ 1 out of 4 chances or 25% chance of happening
->Attack
so assuming the first 4 conditions are always true, the enemy won't attack every time those 4 conditions are true. Instead, the enemy will attack if those 4 conditions are true AND randomly (randomly would have to be configurable like X out of Y chances or in percentage).