1) First you need to select all the files you wish to rename. To select All Files in a folder you can go to Edit > “Select All” or press Ctrl + A. On the other hand you can select Multiple Files by holding down the “Ctrl” Key and selecting individual files with your mouse.
2) Now you can right-click on any of the highlighted files and choose “Rename” or you can press F2, which is the windows shortcut.
3) Now you just need to rename the first file to whatever you wish. Once you rename the first file you can press enter, this will rename all the files you have selected to this name with a unique number appended to the end.