I tried to follow the guide here (How do I move the blockchain (data.mdb) to a different directory during (or after) the initial sync without losing the progress?), but I cannot change the path to my hard drive. The Monero GUI program does not even recognize that I have a hard drive on my computer.
I attached a photo (visible here: https://i.postimg.cc/7ZtQMsmT/ex1.png) and as you can see my hard drive (exthdd) is mounted and recognized by the system but not recognized by the Monero program. Thank you all for all help.