Sokoban mechanics is really simple, all you need is a TileMap and a couple of sprites for the player and crates. Plus maybe some movement behavior like MoveTo.
Programming the logic can be a bit tricky for an inexperienced developer, but it's also not too difficult.
Left key pressed -> check tile to the left of the player -> if it's free, move the player there.
If there is a crate -> check tile to the left of the crate -> if it's free, move both the player and the crate.
etc.