Convert a PNG to a JPEG Using Microsoft Paint

To Convert a PNG to a JPEG Using Microsoft Paint: 

1. In the lower-left corner, click the [Search Windows] icon (magnify glass) > Type "Paint" > Click the [Paint] program. 
2. Select "File" > Select "Open" > Double-click the image file you wish to convert. You should now see the image open in Paint.
3. Click the "File" > Select "Save as".
4. Choose the folder you wish to save your file under. 
5. In the "File name" field, enter a name for the file.
6. From  the "Save as type" drop-down menu, select "JPEG." 
7. Choose the folder where you wish to save the file, then click [Save]. This should save your picture as a new JPEG file and you should still have the old PNG file as well.