LR is a Non-destructive image editing program. It does not change the original file. It store the edits you have made to either the file itself with some files, to the Catalog file and or to a Sidecar XMP file. These changes, edits, will not be seen by other programs when viewing the files. They are only Displayed, Applied, to the image file when you view them in LR.
You can Bake them into a file by exporting the image to another file name or the same file name with a 1 or Edit added to the original file name.
The changes made in Develop module in Lightroom are stored in the catalog.
In order to get the files with the changes, you need to export the images from Lightroom.
Refer the links below :
Let me know if this helps.
And the others have explained, Lightroom does not apply changes to the file. All changes are stored in the catalog and then applied to the image when it is displayed in Lightroom. If you want a copy of the image with all of the changes so that you can share it with others or send it to a lab to be printed, then you need to export a copy of that image using the export dialog in Lightroom.
Lightroom functions this way by design. The images that you import are always left in their original, unmodified state.