How can I upload photos and videos to my computer?

[AC Question]

My phone says it is too full for me to look at photos others send to me, take new photos, and at one time it was too full to receive text messages. I have tried the typical route to save them to my google drive (go into my Gallery, select up to 100 photos at a time, then choose to upload to my Google drive), but despite me spending hours doing that, when I go to my Google drive the photos are not there, and when I click on my Gallery on my phone, I can't even view my photos anymore, so I can't tell it to upload so that I can then delete them from my phone. I have tried restarting my phone several times, before when I could see my Gallery photos I was able to upload some to my Google drive and deleted hundreds off my phone after that, but now I'm stuck. I know what I need to do, but I don't seem to be able to do it. Please help!