How can change some text above a character upon collision in Unreal?

I've just started using Unreal Engine, and I was trying to do a super simple game where there is a character that has text above his head that says 'Bag 'o' fries.'

My plan was to have it so if something touches the bag 'o' fries, the text changes to 'Mission Complete.' I currently have one blueprint that just says onGameStart --> BoxOverlapActors --> set variable 'text' to 'Mission Complete'. The variable 'text' I made isn't actually connected to the text, so this is where I have the problem.

How can I do this?