If you google "Image Resizer Powertoy for Windows" you will find an app that once you install it all you have to do is right-click the photo and it gives you options on the size you want it to be.
Go to Advanced and make sure the "resize orginal picture" is NOT checked. This will make a copy of the photo, which is what you want.
They have preset sizes you can click, or you can go Advanced and choose the dimensions you want.
It is the tool I use to resize photos for the forums.
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