I need to copy all the files within a main folder called Videos on my desktop which was created by my os (not by me, came with os iso), it's where I store my videos. Within that is another 2nd folder called videos too (and other stuff). I need to copy everything from main folder Videos to my external drive called One Touch.

On the external drive called One Touch the main folder called Videos does not exist but all it's contents are do. Recently I have tidied up the main Videos folder on the desktop so right now it does not resemble what's on external drive. Do I need to delete everything on external drive and start again? And also since the main Video folder does not exist will rysnc create that if I use this below:


Also I used
double space inadvertently after dry-run and it appears its copying everything over as it's taking a while usually dry-run only last few seconds, and it's been a few minutes. I guess a double space after dry-run means it won't be a dry run?

How do I tell it to stop or pause copying everything in terminal?

It's an option --dry-run (or -n)
The Double space does not harm.

I don't know if this will create a missing Videos/ on the destination.
But the following will for sure:
Now it's told to copy the Videos directory itself, not its contents.

The --dry-run with double space after it actually copied everything over, i.e. it didn't work as dry run.

If I need to stop rync for any reason whilst it's running what command should I use?

That is almost impossible. I would rather say you forgot -- before dry-run (like in your post #20). Parsing command line (including spaces between arguments) processed by the shell before even starting the execution of the command (rsync) and the shell does not care about the number of those characters.

Ctrl-C should work in most cases (not only with rsync).