As has been said above, we need more information.
It looks like you're using a Windows PC (rather than, say, an iPad or similar) but confirmation of that would be helpful, please. (Also, which version of Windows are you using? e.g. Vista, 7, 8, 10 or 11).
Can you actually open the Documents folder (or wherever else you've stored the relevant files)? If so, what then happens when you double-click on a file? (Nothing at all? An error message? If so, what does it say?).
If you open OpenOffice and go to File > Open, can you see your documents listed in the relevant folder? If so, what happens when you try to open one of them?