Help with making NPC GUI

I'm trying to make a custom mob to bind to a GUI that acts like the NPC mob, in Bedrock, but it can still run around and do normal mob stuff, idk.

I'm basically making a chatbot, with a set of dialogs that I have made, but I barely know how to do it.

I was thinking of making a ton of GUIs, and the buttons, in said GUIs, would change to another GUI, to continue the dialog. (Don't know if that made sense)

Or have one GUI, but has many procedures to change the text label, add buttons, and name those buttons.

I want to know if this is possible, mainly with changing the text on a label.