I am trying to get pics off my Galaxy S6 but now it is saying no pics or video found

[AC Question]

I am trying to get pics off my phone but now it is saying no pics or video found

I have a lot of pics on my galaxy 6S to the point to where it keeps wanting me to buy more storage so I am trying to get most of them off of it and onto my computer. Oh! and I need step by step instructions, bc I am not the best with computers, Thank You!!!!