First, set the file extension not to be hidden in the folder option, and then modify the suffix name in the attribute interface. Please refer to the following steps for specific operations.
1. First, go to any folder on the computer and click Folder Options in the Tools drop-down menu.
2. Then, on the view page of the window, uncheck "Hide extensions of known file types", and click OK.
3. Then find the file to change the attribute in the computer, select it, click the right mouse button, and click the "Attribute" option in the right-click menu.
4. Then change the file extension to the desired format in the attribute setting interface, and click OK.
5. Then click "Yes" in the pop-up dialog box to complete the attribute change of suffix. After completing the above settings, you can change the properties of the file.