Can somebody tell me which functions I would need to use to make this pseudocode work?

psuedocode for archer direction and shooting:

make 4 idle direction animations containing first frame
make 4 directional shooting animations with leftover frames

1)when left key is pressed,left idle animation is played infinitely even if left key is lifted.
if left idle animation is playing and spacebar is pressed,left shooting animation/arrow sound is played for as long as spacebar is pressed.
projectile/object is launched in left direction when left shooting animation is played.

on collison with right direction walking monster,monster is defeated and monster death animation/bloodpool/death sound is played.
score of 10 points is added to the score meter.

2)when right key is pressed,right idle animation is played infinitely even if right key is lifed.
if right idle animation is playing and spacebar is pressed,right shooting animation/arrow sound is played for as long as spacebar is pressed.
projectile/object is launched in right direction when right shooting animation is played.

on collison with left direction walking monster,monster is defeated and monster death animation/bloodpool/death sound is played.
score of 10 points is added to the score meter.

3)when down key is pressed,down idle animation is played infinitely even if right key is lifed.
if down idle animation is playing and spacebar is pressed,down shooting animation/arrow sound is played for as long as spacebar is pressed.
projectile/object is launched in down direction when down shooting animation is played.

on collison with up direction walking monster,monster is defeated and monster death animation/bloodpool/death sound is played.
score of 10 points is added to the score meter.

4)when up key is pressed,down idle animation is played infinitely even if up key is lifed.
if up idle animation is playing and spacebar is pressed,up shooting animation/arrow sound is played for as long as spacebar is pressed.
projectile/object is launched in up direction when up shooting animation is played.

on collison with down direction walking monster,monster is defeated and monster death animation/bloodpool/death sound is played.
score of 10 points is added to the score meter.

archer death psuedocode:

if left monster reaches player,Game Over title/game over music is shown onscreen.
if right monster reaches player,Game Over title/game over music is shown onscreen.
if up monster reaches player,Game Over title/game over music is shown onscreen.
if down monster reaches player,Game Over title/game over music is shown onscreen.

monster psuedocode:

right monster spawn point in left direction.
spawn every 2.5 seconds.
play right monster walk animation and move it right until player is reached.
game over if player reached.
blood pool/death animation/death sound played if contact with arrow.

left monster spawn point in right direction.
spawn every 4 seconds.
play left monster walk animation and move it left until player is reached.
game over if player reached.
blood pool/death animation/death sound played if contact with arrow.

down monster spawn point in up direction.
spawn every 3 seconds.
play down monster walk animation and move it down until player is reached.
game over if player reached.
blood pool/death animation/death sound played if contact with arrow.

up monster spawn point in down direction.
spawn every 1.5 seconds.
play up monster walk animation and move it up until player is reached.
game over if player reached.
blood pool/death animation/death sound played if contact with arrow.

Everything in your project is pretty basic.
Learn the Unity and C# basics, than you should get it.

Maybe this one could help:

For any help you can also add me at Skype: Jaudatus