need a help to a simple script

hi. I`m newbie and I try to do a simple script, but I don't know how.
this is how I imagine - player touch the cube - after this 4 arrow appears , one arrow for each direction. if player touch one of arrow the cube will move to that direction. the cube wont move across obstacle`s.the arrows only appears and the cube move only one time. after the player touch the cube and select his direction, even if touch again the arrows won't appears(if an another cube on the left side of the cube n1, only three arrows will appear, where is the cube n2 will not turn up anything and if the player chooses the cube n2, no arrows will appear where cube n1)

can anyone help me with this?

 

I think you need some tutorials. There are some pretty good but a little outdated tutorials here:
http://walkerboystudio.com/html/unity_training___free__.html#unity3game1