Do not draw anything on screen at Bullet_Creation, instead draw all bullets same time in the main loop. You should have the coordinates of each bullet saved in array.

There is example of using dynamic array (i am not sure if all pascal compilers support this, especially oldest):
http://www.delphibasics.co.uk/RTL.asp?Name=Array

But you can just define, say 100 bullets max and have the array size static. If you can't use record such as described in previous posts you can have 2 arrays:
[pascal]BulletX,BulletY: array[0..99] of integer;[/pascal]