If your camera creates files with unhelpful names instead of date/time within the filename (e.g. "_A123456.JPG") , as long as there is Exif data within the image files, you can use

exiftool -fileOrder DateTimeOriginal -recurse -extension jpg -extension jpeg -ignoreMinorErrors '-FileName<${CreateDate}_%f.jpg' -d IMG_%Y-%m-%d_%H-%M-%S_%%.3nc ./

to rename them.

See https://exiftool.org/

ExifTool by Phil Harvey

A command-line application and Perl library for reading and writing EXIF, GPS, IPTC, XMP, makernotes and other meta information in image, audio and video files. For Windows, MacOS, and Unix systems.

I added the following alias to my ~/.bashrc:

alias exif-rename='exiftool -fileOrder DateTimeOriginal -recurse -extension jpg -extension jpeg -ignoreMinorErrors '\''-FileName<${CreateDate}_%f.jpg'\'' -d IMG_%Y-%m-%d_%H-%M-%S_%%.3nc'

so I can invoke it using "exif-rename ./_A*".

Also I love the https://exiftool.org/#comments section including gems like:
ExifTool by Phil Harvey

A command-line application and Perl library for reading and writing EXIF, GPS, IPTC, XMP, makernotes and other meta information in image, audio and video files. For Windows, MacOS, and Unix systems.