You need to take out the SD card and use a computer for image burning, and it can be roughly divided into 3 steps:

1. Download the mirror

CrowPi2 release_v1.2.0 20210305 

2. Format the memory card

Using SDFormatter software to format the SD card.

You can download this software from the download link at the bottom of this comment.

3. Install the image

Using Win32DiskImager software to install the iamge, which is very easy to operate.

You can download it from the download link at the bottom of this comment, too.

After you have burned the image, inserting the memory card into the Raspberry Pi of CrowPi2, and then turn it on.

SDFormatter and Win32DiskImager Download

If you want to install emacs, check this link for package updates:

https://forums.raspberrypi.com/viewtopic.php?t=318242