I bought an Ardunio Pro Mini for use of running a HUD system through an OLED screen. My question is, can I upload software from my PC to my controller? If I were to view the program's code and upload it individually? I really don't know very much.
If you think about it the Arduino (if that is what you mean by "controller") would be pretty useless if you could not upload code to it from your PC
Have you got the Arduino IDE installed ?
What code do you have ?
Where did the code come from ?
What hardware do you have ?
Hi,
Yes you can upload you code to the Pro Mini, but you need an FTDI module to connect your USB to the Pro Mini serial port.
This should give you the information you need.
https://learn.sparkfun.com/tutorials/using-the-arduino-pro-mini-33v/all
Have you got the 5V or 3V3 powered Pro Mini?
Have you written code for Arduino and uploaded it before?
Can you tell us your electronics, programming, arduino, hardware experience?
For what reason did you purchase a Pro Mini?
Thanks.. Tom.. 
Tom...