Hello @adepounds! I'm happy with your sincerity and decision to write this, a lot of people prefer to just ignore the fact or continue posting uncredited content.
If they haven't explained it to you yet, here's a simple summary:

Images can be taken from any source (PROVIDED YOU CITE THEM BELOW), or they can be taken from free image sites such as Pixabay.
But still, it is necessary to credit, as follows:

copy the direct link from the image ---> paste in the text ---> use the command [ and ] to write "source" for example, and followed by ( and ) where the link will be. This command makes a "hyperlink" as I did there in the 'pixabay'.

If this got confusing, I suggest you read posts like this one, for example that will help with the formatting.

But your suggestion about DV is very pertinent, I even ask @scholaris to take a look here. We need to think of a fixed post for everyone to know how to avoid plagiarism and also DownVotes.