How to make UI buttons so my player can move along certain lines

I am making 2D games where my player has 3 lines and he has to avoid enemies, l made it so he can avoid it with keyboard, but l want my game on android so he can move with buttons. Please answer if u see this. I want that when l my player touches UP button he goes on top line and DOWN button so he can move in the middle or in the bottom line. It`s like 0 for middle, 1.5 for top line and -1.5 for bottom line.