AI for check obstacle

Currently I am making a game that have a player controlled by move left and right (user arrow on keyboard). The goal is to avoid walls in front of player by controlling player to left and right. I know I am very new in using Unity and Game Development, I am just curious on how using AI in a game. So thats why I want to know how to controlling the player using AI (not using input keyboard arrow left and arrow right). I have do some research in google, and suggest using Pathfinding A*. But it's look like difficult to understand and implemented on my game. All I want is detect if there is a wall in front of player, if wall is available the player move to left or right. Just it. The question is, what kind AI to implementation that ?