Is there a way to have my character 'look at' another character or object at a certain point.
Right now, I have my character talk, I use the 'Look at' functionality but then the character immediately turns his head, what I want is to turn his head when I want and then to turn his head back.

In conversation you want them to switch back and forth. 

I noted this bit of guidance from a reallusion page, but I cannot see where you would set this time range.

You can have the actor Look At the target object over a certain period of time and then have it stop looking outside that time range.