Unit should appear and go forward

Hello everyone, I have an idea for the game (this is related to the story/lore about the life of the main character). And there will be one mission: It will be necessary to build a house and one unit will go out of it), BUT this unit should go only on the brown road and only forward. How can I implement this function? To unit "born" from the house and go forward.

P.S. Since I am a beginner, I don’t even know where to start and what articles to read. Someone told me that I should study raycast, but I'm not sure


Approximate mockup of my idea: https://drive.google.com/open?id=11KkEx96Ehm11p21UcPTJllMXe9Wd_7ep

 

Before you dive in to making a game, you'll definitely want to take the time to learn your way around Unity. Try starting here and building out your skillset before jumping into a full game: https://learn.unity.com/course/unity-basics

 

I think making games is a great way to learn Unity! Making small and simple games, discovering new things every day... If you try to learn by theoretics only you will get bored really quickly...