Downloading from SD card

[Drummermouse]

I have an SD card in my Galaxy S9 phone on which I have saved loads of photos but when I try to download via a cable onto my computer it will only download the photos saved on the internal storage
How do I gain access to these other photos or can I transfer them from the SD to the internal storage?

 

[Drummermouse]

OK thanks. I've tried fitting the Micro SD in my reader but it doesn't seem to read it but I will give the USB OTG a try.