Can't change COM1

Hi There,

The only COM port showing on my "Tools" menu is COM1 - How do I change it to COM3 please.

You don’t , COM1 is usually an internal port on the computer motherboard and nothing to do with what you have plugged in.
When you plug your Arduino in it should appear as another port .
If it doesn’t you most likely have a USB lead issue ( you don’t have a data type lead) or you have a clone Arduino that needs a different driver install .
Can you put up more detail of the Arduino you have , computer you are using and version of the IDE .

It was my lead, thank you so much. It’s been a very frustrating morning