Moderator Notice
Please don't hijack other threads, your problem has nothing to do with the Tag Browser or using the keyboard
Try using Save to Disk->Save single format to disk.
But EPUB on Kindle - is that the best format for that device. And why not use calibre's Send to device feature, which is one the main purposes of calibre. Have you watched the
Video Tutorials - they're probably the best way to get started with calibre - watch a bit, try it out, watch a bit, try it...
BR