All the edits you do in Lightroom are automatically saved to the catalog.
If you want a copy of the file to use outside LR, use Export.
If you want to export with the original pixel dimensions, make sure that Resize to fit is unchecked.
You Export them to the File Type you want to use. TIF for the highest quality and useabilty across any system, PSD for high quality and to be used only with Adobe software or JPG.
You need to read up on how LR works. LR never changes the original image. It just Adds the edits you have done when viewing that image inside LR.
To have those edits Burned Into the image file you have to export it with a different file extension (Type) or different file name if you are using the same extension.