Correct.

ok. And I can do it where if the TimeDate is different OR the FileSize is different? Either/or, right?

This is a new program to me so I'm just learning it.

You can select this both for synchronization:
https://winscp.net/eng/docs/ui_synchronize

and Compare Directories function:
https://winscp.net/eng/docs/ui_pref_commander

I was thinking of the TimeDate + FileSize as another option. If one is different, consider it different. If both are different, consider it different.

I suggest an option to pick. FileZilla does that.

And what if only one is different?

Use both size + date in combination together for determining whether a file is different.

Both must be the same for the file to be considered the same. And both must be different for the file to be considered different.