Com port in Arduino IDE greyed but can program Arduino pro mini

Aim: I'm trying a sketch to read Voltages via Arduino pro mini. I can upload the sketch to the Arduino fine (I used the blink program, which works fine). The problem is when I go to use the serial monitor, I get "board at null is not available" which from my understanding means the com port isn't set? When I go to select the com port it is greyed out. When I go to device manager to see what com port is assigned, there are none. I have provided an image of what my Arduino is coming up as in device manager and the driver that I used via the zadig tool recommended by sparkfun.

What are you using to program the promini and what settings have you selected?

Hardware: I am using the sparkfun avr pocket programmer.

In Arduino > Tools > I have Arduino pro mini selected.
Arduino > Tools > Processor "ATmega328p (5V, 16MHz)
Arduino > Tools > Programmer "USBTinyISP"

I did just read that USBtiny isn't a serial device and can't create one. Would this be my problem? If it is, is there anything I can do to achieve my aim?

Yes, that is your problem. The solution is to buy a so-called FTDI cable (e.g. FTDI Cable 5V - DEV-09718 - SparkFun Electronics; this one is 5V, there is a 3.3V version as well) or a TTL-to-USB converter (e.g. SparkFun USB to Serial Breakout - FT232RL - BOB-12731 - SparkFun Electronics).

You did already buy a programmer but would have been the better choice; it offers all the functionalities that you need (ISP programmer as well as TTL-to-USB converter). Those that have it (I have the V2.0) are convinced that it's the best you can buy for the given purpose.

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Wicked. Thanks mate. I'll go the pololu then, mob in Australia sell them for a reasonable price.

This probably wasn't your problem but I was setting up for a new python sketch for ESP32 but Tools>>Port was greyed out. I chased around, installed PySerial. Still no Port options. Then I plugged in the board and Voila!

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